A carcinogen is any substance, radionuclide, or radiation that promotes carcinogenesis, the formation of cancer. This may be due to the ability to damage the genome or to the disruption of cellular metabolic
processes. Several radioactive substances are considered carcinogens,
but their carcinogenic activity is attributed to the radiation, for
example gamma rays and alpha particles, which they emit. Common examples of non-radioactive carcinogens are inhaled asbestos, certain dioxins, and tobacco
smoke. Although the public generally associates carcinogenicity with
synthetic chemicals, it is equally likely to arise in both natural and
synthetic substances. Carcinogens are not necessarily immediately toxic; thus, their effect can be insidious.
Cancer is any disease in which normal cells are damaged and do not undergo programmed cell death as fast as they divide via mitosis. Carcinogens may increase the risk of cancer by altering cellular metabolism or damaging DNA directly in cells, which interferes with biological
processes, and induces the uncontrolled, malignant division, ultimately
leading to the formation of tumors. Usually, severe DNA damage leads to
programmed cell death, but if the programmed cell death pathway is
damaged, then the cell cannot prevent itself from becoming a cancer
cell.
Co-carcinogens
are chemicals that do not necessarily cause cancer on their own, but
promote the activity of other carcinogens in causing cancer.
After the carcinogen enters the body, the body makes an attempt to eliminate it through a process called biotransformation. The purpose of these reactions is to make the carcinogen more water-soluble
so that it can be removed from the body. However, in some cases, these
reactions can also convert a less toxic carcinogen into a more toxic
carcinogen.
DNA is nucleophilic; therefore, soluble carbon electrophiles are carcinogenic, because DNA attacks them. For example, some alkenes are toxicated by human enzymes to produce an electrophilicepoxide. DNA attacks the epoxide, and is bound permanently to it. This is the mechanism behind the carcinogenicity of benzo[a]pyrene in tobacco smoke, other aromatics, aflatoxin and mustard gas.
Carcinogenicity: Ability or tendency to produce cancer.
Note: In general, polymers are not known as carcinogens or mutagens, however, residual monomers or additives can cause genetic mutations.
Radiation
CERCLA identifies all radionuclides as carcinogens, although the nature of the emitted radiation (alpha, beta, gamma, or neutron and the radioactive strength), its consequent capacity to cause ionization
in tissues, and the magnitude of radiation exposure, determine the
potential hazard. Carcinogenicity of radiation depends on the type of
radiation, type of exposure, and penetration. For example, alpha radiation
has low penetration and is not a hazard outside the body, but emitters
are carcinogenic when inhaled or ingested. For example, Thorotrast, a (incidentally radioactive) suspension previously used as a contrast medium in x-ray diagnostics, is a potent human carcinogen known because of its retention within various organs
and persistent emission of alpha particles. Low-level ionizing
radiation may induce irreparable DNA damage (leading to replicational
and transcriptional errors needed for neoplasia or may trigger viral
interactions) leading to pre-mature aging and cancer.
Not all types of electromagnetic radiation are carcinogenic. Low-energy waves on the electromagnetic spectrum including radio waves, microwaves, infrared radiation and visible light
are thought not to be, because they have insufficient energy to break
chemical bonds. Evidence for carcinogenic effects of non-ionizing
radiation is generally inconclusive,
though there are some documented cases of radar technicians with
prolonged high exposure experiencing significantly higher cancer
incidence.
Higher-energy radiation, including ultraviolet radiation (present in sunlight), x-rays, and gamma radiation, generally is
carcinogenic, if received in sufficient doses. For most people,
ultraviolet radiations from sunlight is the most common cause of skin
cancer. In Australia, where people with pale skin are often exposed to
strong sunlight, melanoma is the most common cancer diagnosed in people aged 15–44 years.
Substances or foods irradiated with electrons or electromagnetic radiation (such as microwave, X-ray or gamma) are not carcinogenic. In contrast, non-electromagnetic neutron radiation produced inside nuclear reactors can produce secondary radiation through nuclear transmutation.
In prepared food
Chemicals used in processed and cured meat such as some brands of bacon, sausages and ham may produce carcinogens.
For example, nitrites used as food preservatives in cured meat such as
bacon have also been noted as being carcinogenic with demographic links,
but not causation, to colon cancer. Cooking food at high temperatures, for example grilling or barbecuing
meats, may also lead to the formation of minute quantities of many
potent carcinogens that are comparable to those found in cigarette smoke
(i.e., benzo[a]pyrene). Charring of food looks like coking and tobacco pyrolysis,
and produces carcinogens. There are several carcinogenic pyrolysis
products, such as polynuclear aromatic hydrocarbons, which are converted
by human enzymes into epoxides, which attach permanently to DNA. Pre-cooking meats in a microwave oven
for 2–3 minutes before grilling shortens the time on the hot pan, and
removes heterocyclic amine (HCA) precursors, which can help minimize the
formation of these carcinogens.
There is a strong association of smoking with lung cancer; the lifetime risk of developing lung cancer increases significantly in smokers. A large number of known carcinogens are found in cigarette smoke. Potent carcinogens found in cigarette smoke include polycyclic aromatic hydrocarbons (PAH, such as benzo[a]pyrene), Benzene, and Nitrosamine. The tar from cigarette smoke is similar to that of marijuana smoke and contains similar carcinogens.
Mechanisms of carcinogenicity
Carcinogens can be classified as genotoxic or nongenotoxic. Genotoxins cause irreversible genetic damage or mutations by binding to DNA. Genotoxins include chemical agents like N-nitroso-N-methylurea (NMU) or non-chemical agents such as ultraviolet light and ionizing radiation. Certain viruses can also act as carcinogens by interacting with DNA.
Nongenotoxins do not directly affect DNA but act in other ways to
promote growth. These include hormones and some organic compounds.
Classification
Approximate equivalences between classification schemes
IARC
GHS
NTP
ACGIH
EU
Group 1
Cat. 1A
Known
A1
Cat. 1
Group 2A
Cat. 1B
Reasonably suspected
A2
Cat. 2
Group 2B
Cat. 2
A3
Cat. 3
Group 3
A4
Group 4
A5
International Agency for Research on Cancer
The International Agency for Research on Cancer (IARC) is an intergovernmental agency established in 1965, which forms part of the World Health Organization of the United Nations. It is based in Lyon, France. Since 1971 it has published a series of Monographs on the Evaluation of Carcinogenic Risks to Humans that have been highly influential in the classification of possible carcinogens.
Group 1:
the agent (mixture) is definitely carcinogenic to humans. The exposure
circumstance entails exposures that are carcinogenic to humans.
Group 2A:
the agent (mixture) is probably carcinogenic to humans. The exposure
circumstance entails exposures that are probably carcinogenic to humans.
Group 2B:
the agent (mixture) is possibly carcinogenic to humans. The exposure
circumstance entails exposures that are possibly carcinogenic to humans.
Group 3: the agent (mixture or exposure circumstance) is not classifiable as to its carcinogenicity to humans.
Group 4: the agent (mixture) is probably not carcinogenic to humans.
Globally Harmonized System
The Globally Harmonized System of Classification and Labelling of Chemicals (GHS) is a United Nations
initiative to attempt to harmonize the different systems of assessing
chemical risk which currently exist (as of March 2009) around the world.
It classifies carcinogens into two categories, of which the first may
be divided again into subcategories if so desired by the competent
regulatory authority:
Category 1: known or presumed to have carcinogenic potential for humans
Category 1A: the assessment is based primarily on human evidence
Category 1B: the assessment is based primarily on animal evidence
American Conference of Governmental Industrial Hygienists
The American Conference of Governmental Industrial Hygienists (ACGIH) is a private organization best known for its publication of threshold limit values
(TLVs) for occupational exposure and monographs on workplace chemical
hazards. It assesses carcinogenicity as part of a wider assessment of
the occupational hazards of chemicals.
Group A1: Confirmed human carcinogen
Group A2: Suspected human carcinogen
Group A3: Confirmed animal carcinogen with unknown relevance to humans
Category 1: Substances known to be carcinogenic to humans.
Category 2: Substances which should be regarded as if they are carcinogenic to humans.
Category 3: Substances which cause concern for humans, owing to
possible carcinogenic effects but in respect of which the available
information is not adequate for making a satisfactory assessment.
This assessment scheme is being phased out in favor of the GHS scheme
(see above), to which it is very close in category definitions.
Safe Work Australia
Under a previous name, the NOHSC, in 1999 Safe Work Australia published the Approved Criteria for Classifying Hazardous Substances [NOHSC:1008(1999)].
Section 4.76 of this document outlines the criteria for classifying
carcinogens as approved by the Australian government. This
classification consists of three categories:
Category 1: Substances known to be carcinogenic to humans.
Category 2: Substances that should be regarded as if they were carcinogenic to humans.
Category 3: Substances that have possible carcinogenic effects in
humans but about which there is insufficient information to make an
assessment.
Procarcinogen
A procarcinogen is a precursor to a carcinogen. One example is nitrites when taken in by the diet. They are not carcinogenic themselves, but turn into nitrosamines in the body, which can be carcinogenic.
Common carcinogens
Occupational carcinogens
Occupational carcinogens are agents that pose a risk of cancer in several specific work-locations:
Major carcinogens implicated in the four most common cancers worldwide
In
this section, the carcinogens implicated as the main causative agents
of the four most common cancers worldwide are briefly described. These
four cancers are lung, breast, colon, and stomach cancers. Together
they account for about 41% of worldwide cancer incidence and 42% of
cancer deaths (for more detailed information on the carcinogens
implicated in these and other cancers, see references).
Lung cancer
Lung cancer
(pulmonary carcinoma) is the most common cancer in the world, both in
terms of cases (1.6 million cases; 12.7% of total cancer cases) and
deaths (1.4 million deaths; 18.2% of total cancer deaths).
Lung cancer is largely caused by tobacco smoke. Risk estimates for
lung cancer in the United States indicate that tobacco smoke is
responsible for 90% of lung cancers. Other factors are implicated in
lung cancer, and these factors can interact synergistically with smoking
so that total attributable risk adds up to more than 100%. These
factors include occupational exposure to carcinogens (about 9-15%), radon (10%) and outdoor air pollution (1-2%).
Tobacco smoke is a complex mixture of more than 5,300 identified
chemicals. The most important carcinogens in tobacco smoke have been
determined by a “Margin of Exposure” approach.
Using this approach, the most important tumorigenic compounds in
tobacco smoke were, in order of importance, acrolein, formaldehyde,
acrylonitrile, 1,3-butadiene, cadmium, acetaldehyde, ethylene oxide, and
isoprene. Most of these compounds cause DNA damage by forming DNA
adducts or by inducing other alterations in DNA.
DNA damages are subject to error-prone DNA repair or can cause
replication errors. Such errors in repair or replication can result in
mutations in tumor suppressor genes or oncogenes leading to cancer.
Breast cancer
Breast cancer is the second most common cancer [(1.4 million cases, 10.9%), but ranks 5th as cause of death (458,000, 6.1%)]. Increased risk of breast cancer is associated with persistently elevated blood levels of estrogen.
Estrogen appears to contribute to breast carcinogenesis by three
processes; (1) the metabolism of estrogen to genotoxic, mutagenic
carcinogens, (2) the stimulation of tissue growth, and (3) the
repression of phase II detoxification enzymes that metabolize ROS leading to increased oxidative DNA damage. The major estrogen in humans, estradiol, can be metabolized to quinone derivatives that form adducts with DNA.
These derivatives can cause dupurination, the removal of bases from
the phosphodiester backbone of DNA, followed by inaccurate repair or
replication of the apurinic site leading to mutation and eventually
cancer. This genotoxic mechanism may interact in synergy with estrogen
receptor-mediated, persistent cell proliferation to ultimately cause
breast cancer.
Genetic background, dietary practices and environmental factors also
likely contribute to the incidence of DNA damage and breast cancer risk.
Colon cancer
Colorectal cancer is the third most common cancer [1.2 million cases (9.4%), 608,000 deaths (8.0%)]. Tobacco smoke may be responsible for up to 20% of colorectal cancers in the United States. In addition, substantial evidence implicates bile acids as an important factor in colon cancer. Twelve studies (summarized in Bernstein et al.)
indicate that the bile acids deoxycholic acid (DCA) and/or lithocholic
acid (LCA) induce production of DNA-damaging reactive oxygen species
and/or reactive nitrogen species in human or animal colon cells.
Furthermore, 14 studies showed that DCA and LCA induce DNA damage in
colon cells. Also 27 studies reported that bile acids cause programmed
cell death (apoptosis). Increased apoptosis can result in selective survival of cells that are resistant to induction of apoptosis.
Colon cells with reduced ability to undergo apoptosis in response to
DNA damage would tend to accumulate mutations, and such cells may give
rise to colon cancer. Epidemiologic studies have found that fecal bile acid concentrations
are increased in populations with a high incidence of colon cancer.
Dietary increases in total fat or saturated fat result in elevated DCA
and LCA in feces and elevated exposure of the colon epithelium to these
bile acids. When the bile acid DCA was added to the standard diet of
wild-type mice invasive colon cancer was induced in 56% of the mice
after 8 to 10 months. Overall, the available evidence indicates that DCA and LCA are centrally important DNA-damaging carcinogens in colon cancer.
Stomach cancer
Stomach cancer is the fourth most common cancer [990,000 cases (7.8%), 738,000 deaths (9.7%)]. Helicobacter pylori infection is the main causative factor in stomach cancer. Chronic gastritis (inflammation) caused by H. pylori is often long-standing if not treated. Infection of gastric epithelial cells with H. pylori results in increased production of reactive oxygen species (ROS).
ROS cause oxidative DNA damage including the major base alteration
8-hydroxydeoxyguanosine (8-OHdG). 8-OHdG resulting from ROS is
increased in chronic gastritis. The altered DNA base can cause errors
during DNA replication that have mutagenic and carcinogenic potential.
Thus H. pylori-induced ROS appear to be the major carcinogens in
stomach cancer because they cause oxidative DNA damage leading to
carcinogenic mutations. Diet is thought to be a contributing factor in
stomach cancer - in Japan where very salty pickled foods are popular,
the incidence of stomach cancer is high. Preserved meat such as bacon,
sausages, and ham increases the risk while a diet high in fresh fruit
and vegetables may reduce the risk. The risk also increases with age.
Slash-and-burn approach to deforest land for agriculture and effects of climate change due to unusually longer dry season and above average temperatures around worldwide during July and August
The 2019 Amazon rainforest wildfires season saw a year-to-year surge in fires occurring in the Amazon rainforest and Amazon biome within Brazil, Bolivia, Paraguay, and Peru during that year's Amazonian tropical dry season. Fires normally occur around the dry season as slash-and-burn methods are used to clear the forest to make way for agriculture, livestock, logging, and mining, leading to deforestation of the Amazon rainforest.
Such activity is generally illegal within these nations, but
enforcement of environmental protection can be lax. The increased rates
of fire counts in 2019 led to international concern about the fate of
the Amazon rainforest, which is the world's largest carbon dioxide sink and plays a significant role in global climate change.
The increased rates were first reported by Brazil's National Institute for Space Research (Instituto Nacional de Pesquisas Espaciais,
INPE) in June and July 2019 through satellite monitoring systems, but
international attention was drawn to the situation by August 2019 when NASA corroborated INPE's findings, and smoke from the fires, visible from satellite imagery, darkened the city of São Paulo despite being thousands of kilometers from the Amazon. As of August 29, 2019,
INPE reported more than 80,000 fires across all of Brazil, a 77%
year-to-year increase for the same tracking period, with more than
40,000 in the Brazil's Legal Amazon (Amazônia Legal
or BLA), which contains 60% of the Amazon. Similar year-to-year
increases in fires were subsequently reported in Bolivia, Paraguay and
Peru, with the 2019 fire counts within each nation of over 19,000,
11,000 and 6,700, respectively, as of August 29, 2019. It is estimated that over 906 thousand hectares (2.24×106 acres; 9,060 km2; 3,500 sq mi) of forest within the Amazon biome has been lost to fires in 2019. In addition to the impact on global climate, the fires created environmental concerns from the excess carbon dioxide and carbon monoxide within the fires' emissions, potential impacts on the biodiversity of the Amazon, and threats to indigenous tribes that live within the forest.
The increased rate of fires in Brazil has raised the most concerns as international leaders, particularly French president Emmanuel Macron, and environmental non-government organizations (ENGOs) attributed these to Brazilian president Jair Bolsonaro's
pro-business policies that had weakened environmental protections and
have encouraged deforestation of the Amazon after he took office in
January 2019. Bolsonaro initially remained ambivalent and rejected
international calls to take action, asserting that the criticism was
sensationalist. Following increased pressure from the international
community at the 45th G7 summit and a threat to reject the pending European Union–Mercosur free trade agreement,
Bolsonaro dispatched over 44,000 Brazilian troops and allocated funds
to fight the fires, and later signed a decree to prevent such fires for a
sixty day period.
Other Amazonian countries have been more open for aid and reduce the rate of fires. While Bolivian president Evo Morales
was similarly blamed for past policies that encouraged deforestation,
Morales has since taken proactive measures to fight the fires and seek
aid from other countries. At the G7 summit, Macron negotiated with the
other nations to allocate US$22 million for emergency aid to the Amazonian countries affected by the fires.
The Amazon forest and deforestation
There are 670 million ha (1.7 billion acres; 6.7 million km2; 2.6 million sq mi) of Amazon rainforest. Human-driven deforestation of the Amazon rainforest has been a major concern for decades as the rainforest's impact on the global climate has been measured. From a global climate perspective, the Amazon has been the world's largest carbon dioxide sink, and estimated to capture up to 25% of global carbon dioxide generation into plants and other biomass. Without this sink, atmospheric carbon dioxide
concentrations would increase and contribute towards higher global
temperatures, thus making the viability of the Amazon a global concern.
Further, when the forest is lost through fire, additional carbon
dioxide is released to the atmosphere, and could potentially contribute
significantly to the total carbon dioxide content. The flora also generates significant quantities of water vapor through transpiration which travel large distances to other parts of South America via atmospheric rivers and contribute to the precipitation in these areas. Due to ongoing global climate change,
environmental scientists have raised concerns that the Amazon could
reach a "tipping point" where it would irreversibly die out, the land
becoming more savanna than forest, under certain climate change conditions which are exacerbated by anthropogenic activities.
Human-driven deforestation of the Amazon is used to clear land for agriculture, livestock, and mining, and for its lumber. Most forest is typically cleared using slash-and-burn
processes; huge amounts of biomass are removed by first pulling down
the trees in the Amazon using bulldozers and giant tractors during the
wet season (November through June), followed by torching the tree trunks
several months later in the dry season (July through October). Fires are most common in July though August.
In some cases, workers performing the burn are unskilled, and may
inadvertently allow these fires to spread. While most countries in the
Amazon do have laws and environmental enforcement against deforestation,
these are not well enforced, and much of the slash-and-burn activity is
done illegally.
Deforestation leads to a large number of observed fires across
the Amazon during the dry season, usually tracked by satellite data.
While it is possible for naturally-occurring wildfires to occur in the
Amazon, the chances are far less likely to occur, compared to those in California or in Australia. Even with global warming,
spontaneous fires in the Amazon cannot come from warm weather alone,
but warm weather is capable of exacerbating the fires once started as
there will be drier biomass available for the fire to spread.
Alberto Setzer of INPE estimated that 99% of the wildfires in the
Amazon basin are a result of human actions, either on purpose or
accidentally.
Manmade fires in the Amazon also tend to elevate their smoke into the
higher atmosphere due to the more intense burn of the dry biomass,
compared with naturally occurring wildfires.
Further evidence of the fires being caused by human activity is due to
their clustering near roads and existing agricultural areas rather than
remote parts of the forest.
Fires in Brazil
Past deforestation and fires in Brazil
Location of Amazônia Legal (red) within Brazil
States within Amazônia Legal.
Brazil's role in deforestation of the Amazon rainforest has been a
significant issue since the 1970s, as 60% of the Amazon is contained
within Brazil, designated as the Brazil's Legal Amazon (Amazônia Legal, BLA).
Since the 1970s, Brazil has consumed approximately 12 percent of the
forest, representing roughly 77.7 million ha (192 million acres)—an area
larger than that of the US state of Texas.
Most of the deforestation has been for natural resources for the
logging industry and land clearing for agricultural and mining use. Forest removal to make way for cattle ranching
was the leading cause of deforestation in the Brazilian Amazon from the
mid-1960s on. The Amazon region has become the largest cattle ranching
territory in the world. According to the World Bank, some 80% of deforested land is used for cattle ranching. Seventy per cent of formerly forested land in the Amazon, and 91% of land deforested since 1970, is used for livestock pasture. According to the Center for International Forestry Research
(CIFOR), "between 1990 and 2001 the percentage of Europe's processed
meat imports that came from Brazil rose from 40 to 74 percent" and by
2003 "for the first time ever, the growth in Brazilian cattle
production, 80 percent of which was in the Amazon[,] was largely export
driven."
The Brazilian states of Pará, Mato Grosso, and Rondônia, located along
the southern border of the Amazon rainforest, are in what is called the
"deforestation arc".
Deforestation within Brazil is partially driven by growing demand for beef and soy exports, particularly to China and Hong Kong.
Brazil is one of the largest exporters of beef, accounting for more
than 20% of global trade of the commodity. Brazil exported over 1.6
million tonnes of beef in 2018, the highest volume in recorded history.
Brazil's cattle herd has increased by 56% over the last two decades.
Ranchers wait until the dry season to slash-and-burn to give time for
the cattle to graze.
While slash-and-burn can be controlled, unskilled farmers may end up
causing wildfires. Wildfires have increased as the agricultural sector
has pushed into the Amazon basin and spurred deforestation. In recent years, "land-grabbers" (grileiros)
have been illegally cutting deep into the forest in "Brazil's
indigenous territories and other protected forests throughout the
Amazon".
Number of fires in Brazil's Amazônia Legal between January 1 and August 26 by year, reported by INPE
Past data from INPE has shown the number of fires with the BLA from
January to August in any year to be routinely higher than 60,000 fires
from 2002 to 2007 and as high as 90,000 in 2003. Fire counts have generally been higher in years of drought (2007 and 2010), which are often coupled with El Niño events.
Within international attention on the protection of the Amazon
around the early 2000s, Brazil took a more proactive approach to
deforestation of the Amazon rainforest. In 2004, the Brazilian
government had established the Federal Action Plan for Prevention and
Control of Deforestation in the Amazon (PPCDAM), with the goal to reduce
the rate of deforestation through land use regulation, environmental monitoring,
and sustainable activities, promoted through partnerships at the
federal and private level, and legal penalties for violations. Brazil also invested in more effective measures to fight fires, including fire-fighting airplanes in 2012. By 2014, USAID was teaching the indigenous people how to fight fires.
As a result of enforcement of PPCDAM, the rate of deforestation in the
Brazilian Amazon dropped 83.5% of their 2004 rates by 2012. However, in 2014, Brazil fell into an economic crisis, and as part of that recovery, pushed heavily on its exports of beef and soy to help bolster its economy, which caused a reversal in the falling deforestation rates. The Brazilian government has been defunding scientific research since the economic crisis.
To support PPCDAM, the INPE began developing systems to monitor
the Amazon rainforest. One early effort was the Amazon Deforestation
Satellite Monitoring Project (PRODES), which is a highly-detailed
satellite imagery-based approach to calculate wildfires and
deforestation losses on an annual basis.
In 2015, INPE launched five complementary projects as part of the Terra
Brasilis project to monitor deforestation closer to real-time. Among
these include the Real-Time Deforestation Detection System (DETER)
satellite alert system, allowing them to capture incidents of wildfires
in 15-day cycles.
The daily data is published on the regularly updated Brazilian
Environmental Institute government website, and later corroborated with
the annual and more accurate PRODES data.
By December 2017, INPE had completed a modernization process and
had expanded its system to analyze and share data on forest fires.
It launched its new TerraMA2Q platform—software which adapts
fire-monitoring data software including the "occurrence of irregular
fires".
Although the INPE was able to provide regional fire data since 1998,
the modernization increased access. Agencies that monitor and fight
fires include the Brazilian Federal Environment and Renewable Resources
Agency (IBAMA), as well as state authorities.
The INPE receives its images daily from 10 foreign satellites,
including the Terra and Aqua satellites—part of the NASA's Earth
Observation System (EOS).
Combined, these systems are able to capture the number of fires on a
daily basis, but this number does not directly measure the area of
forest lost to these fires; instead, this is done with fortnightly
imaging data to compare the current state of the forest with reference
data to estimate acreage lost.
Jair Bolsonaro was elected as President of Brazil
in October 2018 and took office in January 2019, after which he and his
ministries changed governmental policies to weaken protection of the
rainforest and make it favorable for farmers to continue practices of
slash-and-burn clearing, thus accelerating the deforestation from previous years. Land-grabbers had used Bolsonaro's election to extend their activities into cutting in the land of the previously isolated Apurinã people in Amazonas where the "world's largest standing tracts of unbroken rainforest" are found. Upon entering office, Bolsonaro cut US$23 million from Brazil's environmental enforcement agency, making it difficult for the agency to regulate deforestation efforts.
Bolsonaro and his ministers had also segmented the environmental
agency, placing part of its control under the agricultural ministry,
which is led by the country's farming lobby, weakened protections on
natural reserves and territories belonging to indigenous people, and
encouraged businesses to file counter-land claims against regions
managed by sustainable forestry practices.
2019 Brazil dry season fires
Agricultural fires in southern Pará, Brazil in August 2019.
INPE alerted the Brazilian government to larger-than-normal growth in
the number of fires through June to August 2019. The first four months
of the year were wetter-than-average, discouraging slash-and-burn
efforts. However, with the start of the dry season in May 2019, the
number of wildfires jumped greatly.
Additionally, NOAA reported that, regionally, the temperatures in the
January-July 2019 period were the second warmest year-to-date on record.INPE reported a year-to-year increase of 88% in wildfire occurrences in June 2019.
There was further increase in the rate of deforestation in July 2019,
with the INPE estimating that more than 1,345 square kilometres
(519 sq mi; 134,500 ha; 332,000 acres) of land had been deforested in
the month and would be on track to surpass the area of Greater London by the end of the month.
The month of August 2019 saw a large growth in the number of
observed wildfires according to INPE. By August 11, Amazonas had
declared a state of emergency. The state of Acre entered into a environmental alert on August 16. In early August, local farmers in the Amazonian state of Pará placed an ad in the local newspaper calling for a queimada
or "Day of Fire" on August 10, 2019, organizing large scale
slash-and-burn operations knowing that there was little chance of
interference from the government. Shortly after, there was an increase in the number of wildfires in the region.
INPE reported on August 20 that it had detected 39,194 fires in the Amazon rainforest since January. This represented a 77 percent increase in the number of fires from the same time period in 2018.
However, the NASA-funded NGO Global Fire Emissions Database (GFED)
shows 2018 as an unusually low fire year compared to historic data from
2004–2005 which are years showing nearly double the number of counted
fires. INPE had reported that at least 74,155 fires have been detected in all of Brazil, which represents a 84-percent increase from the same period in 2018. NASA originally reported in mid-August that MODIS
satellites reported average numbers of fires in the region compared
with data from the past 15 years; the numbers were above average for the
year in the states of Amazonas and Rondônia, but below average for Mato
Grosso and Pará.
NASA later clarified that the data set they had evaluated previous was
through August 16, 2019. By August 26, 2019, NASA included more recent
MODIS imagery to confirm that the number of fires were higher than in
previous years.
INPE satellite imagery of a 70-by-70 mile area along the Purus River between Canutama and Lábrea
in the state of Amazonas, taken on August 16, 2019, showing several
plumes of smoke from wildfires, including areas that have been
deforested
By August 29, 80,000 fires had broken out in Brazil which represents a 77% rise on the same period in 2018, according to BBC.
INPE reported that in the period from January 1 to August 29, across
South America, and not exclusive to the Amazon rainforest, there were
84,957 fires in Brazil, 26,573 in Venezuela, 19,265 in Bolivia, 14,363
in Colombia, 14,969 in Argentina, 10,810 in Paraguay, 6,534 in Peru,
2,935 in Chile, 898 in Guyana, 407 in Uruguay, 328 in Ecuador, 162 in
Suriname, and 11 in French Guiana.
First media reports
While
INPE's data had been reported in international sources earlier, news of
the wildfires were not a major news story until around August 20, 2019.
On that day, the smoke plume from the fires in Rondônia and Amazonas
caused the sky to darken at around 2 p.m. over São Paulo—which is almost 2,800 kilometres (1,700 mi) away from the Amazon basin on the eastern coast. NASA and US National Oceanic and Atmospheric Administration (NOAA) also published satellite imagery from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra satellitein alignment with INPE's own, that showed smoke plumes from the wildfires were visible from space.
INPE and NASA data, along with photographs of the ongoing fires and
impacts, caught international attention and became a rising topic on
social media, with several world leaders, celebrities, and athletes
expressing their concerns.
According to Vox,
of all the concurrent wildfires elsewhere in the world, the wildfires
in the Amazon rainforest in Brazil were the most "alarming".
Responses of the Brazilian government
In the months prior to August 2019, Bolsonaro mocked international
and environmental groups that felt his pro-business actions enabled
deforestation.
At one point in August 2019, Bolsonaro jokingly calling himself
"Captain Chainsaw" while asserting that INPE's data was inaccurate. After INPE announced an 88% increase of wildfires in July 2019, Bolsonaro claimed "the numbers were fake" and fired Ricardo Magnus Osório Galvão, the INPE director. Bolsonaro claimed Galvão was using the data to lead an "anti-Brazil campaign".
Bolsonaro had claimed that the fires had been deliberately started by
environmental NGOs, although he provided no evidence to back up the
accusation. NGOs such as WWF Brasil, Greenpeace, and the Brazilian Institute for Environmental Protection countered Bolsonaro's claims.
Bolsonaro, on August 22, argued that Brazil did not have the
resources to fight the fires, as the "Amazon is bigger than Europe, how
will you fight criminal fires in such an area?".
Historically, Brazil has been guarded about international
intervention into the BLA, as the country sees the forest as a critical
part of Brazil's economy.
Bolsonaro and his government have continued to speak out against any
international oversight of the situation. Bolsaonaro considered French
President Emmanuel Macron's comments to have a "sensationalist tone" and accusing him of interfering in what he considers is a local problem. Of Macron and German Chancellor Angela Merkel,
Bolsonaro stated: "They still haven't realized that Brazil is under new
direction. That there's now a president who is loyal to [the] Brazilian
people, who says the Amazon is ours, who says bad Brazilians can't
release lying numbers and campaign against Brazil."
Bolsonaro's foreign minister Ernesto Araújo
has also condemned the international criticism of Bolsonaro's reaction
to the wildfires, calling it "savage and unfair" treatment towards
Bolsonaro and Brazil.
Araújo stated that: "President Bolsonaro's government is rebuilding
Brazil", and that foreign nations were using the "environmental crisis"
as a weapon to stop this rebuilding.
General Eduardo Villas Bôas, former commander of the Brazilian Army,
considered the criticism of world leaders, like Macron and Canadian
Prime Minister Justin Trudeau, to be directly challenging "Brazilian sovereignty", and may need to be met with military response.
With increased pressure from the international community, Bolsonaro
appeared more willing to take proactive steps against the fires, saying
by August 23, 2019, that his government would take a "zero tolerance"
approach to environmental crimes.
He engaged the Brazilian military to help fight the wildfires on August
24, which Joint Staff member Lt. Brig. Raul Botelho stated was to
create a "positive perception" of the government's efforts. Among military support included 43,000 troops as well as four firefighting aircraft, and an allocated US$15.7 million for fire-fighting operations. Initial efforts were principally located in the state of Rondônia, but the Defense Ministry stated they plan to offer support for all seven states affected by the fires.
On August 28, Bolsonaro signed a decree banning the setting of fires in
Brazil for a period of 60 days, making exceptions for those fires made
purposely to maintain environmental forest health, to combat wildfires,
and by the indigenous people of Brazil. However, as most fires are set
illegally, it is unclear what impact this decree could have.
Rodrigo Maia, president of the Chamber of Deputies,
announced that he would form a parliamentary committee to monitor the
problem. In addition, he said that the Chamber will hold a general
commission in the following days to assess the situation and propose
solutions to the government.
Brazil banned clearing land by setting fire to it on 29 August 2019.
More measures taken by the Brazilian government of Jair Bolsonaro to stop the fires include:
Accepting 4 planes from Chile to battle the fires.
Accepting 12 million dollars of aid from the United Kingdom government
Softening his position about aid from the G7.
Appealing for an international conference to preserve the Amazon
with participation of all countries that have some part of the Amazon
rainforest in their territory
Protests against Brazilian government policies
In regards to the displacement of the indigenous people, Amnesty International
has highlighted the change in protection of lands belonging to the
indigenous people, and have called on other nations to pressure Brazil
to restore these rights, as they are also essential to protecting the
rainforest. Ivaneide Bandeira Cardoso, founder of Kanindé, a Porto Velho-based
advocacy group for indigenous communities, said Bolsonaro is directly
responsible for the escalation of forest fires throughout the Amazon
this year. Cardoso said the wildfires are a "tragedy that affects all of
humanity" since the Amazon plays an important role in the global
ecosystem as a carbon sink to reduce the effects of climate change.
Thousands of Brazilian citizens held protests in several major
cities from August 24, 2019, onward to challenge the government's
reaction to the wildfires. Protesters around the world also held events at Brazilian embassies, including in London, Paris, Mexico City, and Geneva.
In
addition to environmental harm, the slash-and-burn actions leading to
the wildfires have threatened the approximately 306,000 indigenous people in Brazil who reside near or within the rainforest. Bolsanaro had spoken out against the need to respect the demarcation of lands for indigenous people established in the 1988 Constitution of Brazil.
According to a CBC report on Brazil's wildfires, representatives of the
indigenous people have stated that farmers, loggers, and miners,
emboldened by the Brazilian government's policies, have forced these
people out of their lands, sometimes through violent means, and equated
their methods with genocide. Some of these tribes have vowed to fight back against those engaged in deforestation to protect their lands.
International responses
Several international governments and environmental groups raised
concerns at Bolsonaro's stance on the rainforest and the lack of
attempts by his government to slow the wildfires. Among the most vocal
was Macron, given the proximity of French Guiana to Brazil.
Macron called the Amazon wildfires an "international crisis", while
claiming the rainforest produces "20% of the world's oxygen"—a statement
disputed by academics. He said, "Our house is burning. Literally."
Discussion about the fires came into the final negotiations of the EU–Mercosur Free Trade Agreement between the EU and Mercosur, a trade bloc of Argentina, Brazil, Uruguay, and Paraguay. With the wildfires on-going, both Macron and Irish Prime Minister Leo Varadkar have stated they will refuse to ratify the trade deal unless Brazil commits to protecting the environment.
Finance minister of FinlandMika Lintilä suggested the idea of a EU ban on Brazilian beef imports until the country takes steps to stop the deforestation.
Fires in Bolivia
Background
In Bolivia, the annual seasonal chaqueo has become an "entrenched custom" that is currently encouraged by recent political decisions. The forest fires in Bolivia occurred during the dry season but they happened independently of Brazil's fires.
Bolivia has 7.7 percent of the Amazon rainforest within its borders.
The Bolivian Amazon covers 19.402 million hectares (47.94 million
acres) which comprise 37.7 percent of Bolivia's forests and 17.7 percent
of Bolivia's land mass. Bolivia's forests cover a total of 51.407 million hectares (127.03 million acres), including the Chiquitano dry forests which is part of the Amazon biome and a transition zone between the Amazon rainforest and the drier forests of the southern Chaco region.
Santa Cruz Department
By August 16, Bolivia's Santa Cruz had declared a departmental emergency because of the forest fires. From August 18 to August 23, approximately 800 thousand hectares (2.0 million acres) of the Chiquitano dry forests were destroyed, more than what was lost over a typical two-year period. By August 24, the fires had already destroyed 1,011 thousand hectares (2.50 million acres) of forestland in the Santa Cruz and were burning near Santa Cruz, Bolivia. By August 26, wildfires had destroyed over 728 thousand hectares (1.80 million acres) of Bolivia's savanna and tropical forests, according to the Bolivian Information Agency (BIA). Over a period of five days, from August 18 to August 22, 450 thousand hectares (1.1 million acres) of forest near Roboré were destroyed.
On August 25, 4,000 state employees and volunteers were fighting the fires.
By August 25, the Chiquitano has lost 650 thousand hectares
(1.6 million acres) of tropical forest within both the Amazon and the
dry forests, mostly within the Santa Cruz
province; like the Brazil fires, such fires occur during the dry
season, but the number of fires in 2019 were larger than in previous
years. Throughout August, wildfires have been spreading across four states. Jaguars, tapirs, and dozens of endangered species are threatened. By August 26, fires in the Dionisio Foianini Triangle—the
Brazil-Bolivia-Paraguay triangle had destroyed savannah and tropical
forest "near Bolivia's border with Paraguay and Brazil".
President Evo Morales
initially ignored the fires. Juan Quintana, the president's chief of
staff, had said they did not require "foreign firefighting aid". In the week of August 18, Morales dispatched soldiers and three helicopters to fight fires in an area about the size of Oregon. On August 22, Morales contracted the Colorado-based Boeing 747 Supertanker
(also known as Global SuperTanker) to conduct firefighting missions
over the Bolivian Amazon, after having previously refused to call on
external help.
The 747 Supertanker is the largest firefighting aircraft in the world,
which can hold approximately 19,000 gallons of water per trip. Morales has stated that the governments of Spain, Chile, and Paraguay have reached out to him to provide help for fighting the fires.
The government had been trying to determine the cause of the
fires, with the Bolivian land management authority attributing 87% of
the fires to illegal slash-and-burn by farmers.
Multiple NGOs assert that deforestation rates in Bolivia increased 200
percent after the government quadrupled available land for deforestation
to farmers in 2015. The land authority attributed the increase on lax
environmental enforcement.
Political opponents of Morales alleged that the Supreme Decree 3973, a mandate to further beef production in the Amazon region, is a major cause of the Bolivian fires. The Santa Cruz province is a critical area for agriculture and cattle-rearing.
Probioma's Miguel Crespo said that, "It may take up to 200 years
for the forests in Bolivia to heal. I've never seen an environmental
tragedy on this scale ...The government has detonated an environmental
disaster. In large part, this tragedy is the result of the state's
populism and development vision based on agribusiness."
Fires in Paraguay's Pantanal
By August 22, fire emergencies in Paraguay's Alto Paraguay district and the UNESCO protected Pantanal region were issued by its federal government. Paraguay President Mario Abdo Benítez was in close contact with Bolivia's Morales to coordinate response efforts.
By August 17, as wind direction changed, flames from fires in Bolivia
began to enter northern Paraguay's Three Giants natural reserve in the
Paraguayan Pantanal natural region. By August 24, when the situation had
stabilized, Paraguay had lost 39,000 hectares (96,000 acres) in the Pantanal. An Universidad Nacional de Asunción representative lamented the disaster failed to attract as much media attention as the fires in the Amazon rainforest.
While most of the Pantanal regions—140,000 and 195,000 square
kilometres (54,000 and 75,000 sq mi)—is within Brazil's borders in the
state of Mato Grosso do Sul, the natural region also extends into Mato Grosso and portions of Bolivia. It sprawls over an area estimated at between 140,000 and 195,000 square kilometres (54,000 and 75,000 sq mi). Within the Pantanal
natural region, which is located between Brazil and Bolivia, is the
"world's largest tropical wetland area". According one of the engineers
charged with monitoring satellite data showing the "evolution of the
fires", the Pantanal is a "complex, fragile, and high-risk ecosystem
because it's being transformed from a wetland to a productive system". The Pantana is bounded by the Humid Chaco to the south, the Arid Chaco dry forests to the southwest, Cerrado savannas lie to the north, east and southeast, and the Chiquitano dry forests, to the west and northwest, where thousands of hectares burned in Bolivia.
A national parks researcher said that outsiders only know the
Amazon, which is a "shame because the Pantanal is a very important
ecological place". The Paraná River, which flows through Argentina, Brazil and Paraguay, is the "second largest river system in South America".
Fires in Peru
Peru
had nearly twice the growth in the number of fires in 2019 than Brazil,
with most believed to be illegally set by ranchers, miners, and coca growers. Much of the fires are in the Madre de Dios
which borders Brazil and Bolivia, though the fires there are not a
result of those started in the other countries, according to the
regional authority. However, they are still concerned about the impact
of downwind emissions, particularly carbon monoxide, on residents of
Madre de Dios. There were 128 forest fires reported in Peru in August 2019.
Environmental impacts of the fires
Emissions
Images created by the Atmospheric Infrared Sounder which depict carbon monoxide caused by fires in the Amazon region of Brazil from Aug. 8-22, 2019.
Locations of active wildfires (marked in orange) in the Amazon as of 22 August 2019
By August 22, NASA's AIRS published maps of increased carbon monoxide and carbon dioxide resulting from Brazil's wildfires. On the same day, the European Union's Copernicus Climate Change Service reported a "discernible spike" in emissions of carbon monoxide and carbon dioxide generated by the fires.
Areas downwind of the fires have become covered with smoke, which
can potentially last upwards of months at a time if the fires are left
to burn out. Hospitals in cities like Porto Velho
had reported over three times the average number of cases of patients
suffering from the effects of smoke over the same year-to-year period in
August 2019 than in other previous years. Besides hindering breathing,
the smoke can exacerbates patients with asthma or bronchitis and have potential cancer risk, generally affecting the youth and elderly the most.
Biodiversity
Scientists at the Natural History Museum
in London, described how while some forests have adapted to fire as
"important part of a forest ecosystem's natural cycle", the Amazon
rainforest—which is "made up of lowland, wetland forests"—is "not
well-equipped to deal with fire". Other Amazon basin ecosystems, like
the Cerrado region, with its "large savannah, and lots of plants there
have thick, corky, fire resistant stems", is "fire adapted".
Mazeika Sullivan, associate professor at Ohio State University's
School of Environment and Natural Resources, explained that the fires
could have a massive toll on wildlife in the short term as many animals
in the Amazon are not adapted for extraordinary fires. Sloths, lizards, anteaters, and frogs may unfortunately perish in larger numbers than others due to their small size and lack of mobility. Endemic species, like Milton's titi and Mura's saddleback tamarin,
are believed to be beset by the fires. Aquatic species could also be
affected due to the fires changing the water chemistry into a state
unsuitable for life. Long-term effects could be more catastrophic. Parts
of the Amazon rainforest's dense canopy were destroyed by the fires therefore exposing the lower levels of the ecosystem, which then alters the energy flow of the food chain.
International actions
On
August 22, the Bishops Conference for Latin America called the fires a
"tragedy" and urged the UN, the international community, and governments
of Amazonian countries, to "take serious measures to save the world's
lungs". Colombian President Ivan Duque
stated he wanted to lead a conservation pact with the other nations
that share the Amazon rainforest with plans to present this to the UN General Assembly. Duque said, "We must understand the protection of our Mother Earth and our Amazon is a duty, a moral duty."
United Nations Secretary General António Guterres
stated on August 23, that: "In the midst of the global climate crisis,
we cannot afford more damage to a major source of oxygen and
biodiversity."
G7 Summit and emergency aid
Attention to the wildfires increased in the week prior to the G7summit discussions on August 24–26 in Biarritz,
France, led by President Macron. Macron stated his intent to open
discussions related to the wildfires in the Brazilian part of the Amazon
and Bolsonaro's response to them.
Merkel has also backed Macron's statements and planned to make the
issue a part of the G7 discussions; via a spokesperson, Merkel stated:
"The extent of the fires in the Amazon area is shocking and threatening,
not only for Brazil and the other affected countries, but also for the
whole world."
Macron further stated that possible international statute to protect
the rainforest may be needed "if a sovereign state took concrete actions
that clearly went against the interest of the planet". Bolsonaro expressed concern to United States president Donald Trump, that with Brazil not part of the G7, the country would be unrepresented in any such debate.
Trump offered to take the position of the Brazilian government to the
meeting and said that the US government did not agree to discuss the
issue without Brazil's presence.
Trump himself was absent from the environmental portion of the summit
held on August 26, 2019, that discussed the fires and climate change,
though members of his advisory team were in attendance.
During the summit, Macron and Chilean president Sebastián Piñera negotiated with the other nations to authorize US$22 million in emergency funding to Amazonian countries to help fight the fires. The Trump administration did not approve of the measure as the funding set certain requirements on its use.
When the final negotiations were completed, Bolsonaro stated that he
would refuse those funds for Brazil, claiming that Macron's interests
were about protecting France's agricultural business in French Guiana
from Brazil's competition. Bolsonaro also criticised Macron by comparing
the Amazon fires to the Notre-Dame de Paris fire earlier in 2019, suggesting Macron should take care of their internal fires before reaching out internationally. The governors of the states of Brazil most affected by the fires pressured Bolsonaro to accept the aid given.
Bolsonaro later clarified that he would accept foreign aid for the
fires, but only if Brazil has the authority to determine how it is used.
Amazon country summit
Brazil's
Bolsonaro stated on August 28, 2019, that the countries sharing the
Amazon rainforest, excluding Venezuela, will hold a summit in Colombia
on September 6, 2019, to discuss the ongoing Amazon fire situation.
2019 wildfires in the media
The media coverage had also broadly overshadowed the Amazon fires in Bolivia, Peru, and Paraguay by the fires and international impact of those in the BLA. The Amazon wildfires also occurred shortly after major wildfires reported in Greenland and Siberia after a globally hotter-than-average June and July, drawing away coverage of these natural disasters.
Some of these photographs shared on social media were from past fire events in the Amazon or from fires elsewhere. Agence France-Presse and El Comercio published guides to help people "fact-check" on misleading photos.
Celebrity responses to Amazon wildfires
American actor Leonardo DiCaprio
said his environmental organization Earth Alliance is donating $5
million to local groups and indigenous communities to help protect the
Amazon.
On August 26, 2019, Europe's richest man, Bernard Arnault, declared that his LVMH group will donate $11 million to aid in the fight against the Amazon rainforest wildfires.
American restaurateur Eddie Huang said he is going vegan as a result of the 2019 Amazon fires. Khloé Kardashian urged her 98 million Instagram followers to adopt a plant-based diet for the same reason.
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