The current social unrest in Guadeloupe and Martinique has brought international attention back to the critical issue of chlordecone pollution in these Caribbean islands. This highly toxic insecticide, banned since 1993 throughout France and its territories, is currently undergoing intense scientific study to understand its harmful effects on the human body and ecosystems.
Chlordecone has left a permanent scar on the French West Indian population. Throughout the protests that have shaken Guadeloupe and Martinique since the end of November, this highly toxic insecticide has been named as one of the key factors behind the social unrest which was provoked by the Covid-19 situation.
France was forced to postpone implementing a vaccination mandate for health workers there after the measure spurred widespread protests on the French territories in which police officers were injured and journalists attacked. If the people in these islands are hesitant to trust the Covid-19 vaccines, it is because they have been failed by Paris on the chlordecone issue.
Former farm workers, who were exposed to this insecticide for many years in banana plantations, believe that chlordecone is directly connected to specific cancers and neurological diseases. This controversial pesticide is now the subject of several scientific studies aimed at finding out more about its effects on health and the environment.
Chlordecone was first used in banana plantations in Guadeloupe and Martinique in 1972 in a battle against an insect called the banana weevil. Banned in 1976 in the United States, the substance was classified as a probable human carcinogen by the World Health Organisation (WHO) in 1979. France itself did not ban it until 1990. However, a governmental exemption allowed its continued use in the West Indies for three more years, until 1993.
The insecticide which polluted the banana trees, poisoned the soil, which then went into the groundwater, the rivers and all the way to the coast. Much of the islands’ vegetation has also been contaminated as the poison has become ingrained in the soil. As a result, chlordecone has been found in animal pastures and subsequently in meat products.
"At least one third of the agricultural land used for cultivation and breeding and at least one third of the marine coastline have been polluted by chlordecone," said Luc Multigner, epidemiologist and director of research at France’s National Institute of Health and Medical Research, Inserm, speaking with FRANCE 24.
As its molecules disintegrate very slowly in the soil, it is difficult to know how long it will stay in the ecosystem. According to the National Institute for Agricultural Research (INRAE), "it could still be there for anything between one to six centuries".
>> Thousands protest in France's Martinique against insecticide 'impunity'
Almost the entire population poisoned
Chlordecone has poisoned, to varying degrees, more than 90% of the population of the two islands, according to Santé publique France and Inserm. "In terms of the general danger of chlordecone, its intrinsic toxicity is well known," said Multigner, referencing hundreds of published research papers dedicated to exploring this poison.
Research into the health consequences of chlordecone is not new. The first studies took place as early as the 1960s, before it had even been introduced to the West Indies. Researchers detected neurological disorders in laboratory animal tests, but also testicular disorders and liver tumour lesions. In the mid-1970s, scientists then discovered neurological damage and liver enlargement in workers at the chlordecone factory in Hopewell, USA.
A few years later, research showed that chlordecone has hormonal properties. Today, it is considered an endocrine disruptor. "Twenty years ago, when the issue of chlordecone received very little media attention, a series of studies were carried out by Inserm to find out whether this pollution was contaminating the population. We found that the West Indian population had indeed been poisoned, since chlordecone was detected in the blood of most of the people studied," said Multigner. "Once this observation was made, the question was do these traces of chlordecone in the blood cause health problems?"
In the 2000s, the Timoun ("child", in Creole) study led by Inserm highlighted a link between chlordecone exposure levels during pregnancy and an increased risk of premature birth. Numerous data acquired during the follow-up of children born to the Timoun cohort are currently being analysed to understand the impact on their development. Other research is still underway, notably on the evolution of chronic hepatitis.
As early as 2010, the Karuprostate study, coordinated by Multigner and Pascal Blanchet, head of the urology department at Pointe-à-Pitre University Hospital in Guadeloupe, identified a clear link between exposure to this harmful substance and occurrences of prostate cancer.
"We observed that the more men were exposed to chlordecone, the greater their risk of developing prostate cancer", said Multigner. "In the West Indies, the incidence rate of this disease is almost twice as high as the estimated incidence rate in mainland France over the period 2007-2014," according to an Inserm study entitled "Pesticides and health effects" and updated last June.
In this context, the Minister of Agriculture and Food Julien Denormandie announced on November 28 that a decree officially recognising prostate cancer as an occupational illness following the use of this pesticide will be issued "before the end of the year".
New prostate cancer studies
There is much research currently being done on the particular connection between this disease and chlordecone. A new study (Cohorte KP-Caraïbes-Breizh) on prostate cancer, "will pay particular attention to environmental contaminants (including chlordecone) on the evolution of the disease according to the treatments", according to France’s Institute of research in health, environment and work.
Faced with an understandably anxious West Indian population, the National Cancer Institute launched a multidisciplinary research programme on November 9 devoted to investigating the link between exposure to chlordecone in the West Indies and the risk of developing prostate cancer. For five years, researchers from different disciplines (epidemiology, human and social sciences, clinical science) will work on this subject to "further our understanding of the role of chlordecone in the risk of prostate cancer as well as its perception and social consequences in the West Indies".
"The strong presumption of a link between chlordecone exposure in the general population and the risk of prostate cancer occurrence has been confirmed," the authors of the “Pesticides and health effects" study write, noting that "the causality of the relationship [between chlordecone and prostate cancer] is considered likely."
"Until now, all scientific knowledge [on the link between chlordecone and prostate cancer] has had no contradiction," said Multigner.
If there is a scientific consensus, on the political level, it is another matter. On February 1, 2019, French President Emmanuel Macron, who six months earlier had denounced this as an "environmental scandal" and recognised, for the first time, that "the State has its share of responsibility", spoke again on the issue.
"We must not say that it is carcinogenic. It has been established that this product is not good, there have been scientifically recognised cases, but we must not go so far as to say that it is carcinogenic because we are saying something that is not true and we are feeding fears," said Macron at the time.
His statement provoked the indignation of international elected leaders and scientists, including Multigner. The Elysée Palace later claimed it was a "misunderstanding". "The president said that chlordecone pollution was a scandal, that's fine. But to say at the same time: 'It is not carcinogenic’ is contrary to research,” says Multigner.
All the scientific studies carried out so far have helped the authorities put in place successive action plans, which aim to protect, raise awareness and repair the damage caused by this insecticide. Specific measures have been taken. Foodstuffs produced in the West Indies may not contain more chlordecone residues than the maximum limit authorised by the State. In addition, many areas are closed to fishing because the fish are contaminated. These decisions have also had socio-economic consequences, as some farmers and fishermen have no longer been able to continue their professional activities.
The deployment this year of the fourth plan to combat chlordecone pollution has not been enough to calm rising tensions among the population. The Guadeloupean and Martinican associations that filed a complaint against the state in 2006 for "endangering the lives of others" are still waiting for a trial. As a result of the statute of limitations, the case is likely to be dismissed.
This article has been translated from the original in French.