Dear Friends and Colleagues

Compelling Evidence of Human Health Effects of Pesticides

The use of synthetic chemical pesticides (insecticides, herbicides, fungicides, etc.) in agriculture around the world began in the 1950s with the onset of industrial agriculture through the ‘Green Revolution’. Since then, industrial agriculture has come to rely increasingly on the use of these chemicals, many of which have become extremely pervasive and persistent in the environment as a result of their widespread repeated use. Pesticideshave been found in every habitat on earth and are routinely detected in both marine and terrestrial mammals.

A report by Greenpeace examines the growing body of research relating to known and suspected human health effects of pesticides, given that the general population is exposed to a cocktail of pesticides daily through food and polluted air, water and soil. Among the many active ingredients that are potentially dangerous to health are the currently approved organophosphates, chlorpyrifos and malathion. Some groups of people are particularly exposed/vulnerable such as farmers and pesticide applicators, young children and fetuses in the womb. The report cites compelling evidence showing correlations between pesticide exposure and incidences of childhood leukemia, several types of cancer, neurodegenerative diseases such as Parkinson’s and Alzheimer’s disease, and endocrine and immune system disruptions along with transgenerational effects.

The report calls for an urgent paradigm shift from industrial agriculture with its heavy reliance on chemical additives towards the full implementation of ecological farming as the only means of feeding the world healthy and safe food and protecting the ecosystems we live in. With this, it underscores the necessity of a phase-out of synthetic chemical pesticides, through legally binding national and international agreements and targets.

The Executive Summary of the report is reproduced below. The full report can be accessed at

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Third World Network
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Executive Summary

Since 1950, the human population has doubled, yet the area of arable land used to feed these people has increased by only 10%. There are huge pressures to provide food, at low cost, on land that is becoming more and more degraded as nutrients are stripped from the soil. Reliance on external inputs – fertilisers and pesticides – continues to be the short-term solution for large-scale commercially intensive agricultural systems.

Synthetic pesticides have been widely used in industrial agriculture throughout the world since the 1950s. Over time, many of these chemicals have become extremely pervasive in our environment as a result of their widespread repeated use and, in some cases, their environmental persistence. Some take an extremely long time to degrade, such that even those banned decades ago, including DDT and its secondary products, are routinely found in the environment today.

As a consequence of this persistence, and potential hazards to wildlife, effect-related research on the impact of pesticides has increased exponentially over the past 30 years (K๖hler and Triebskorn 2013). It is now clear that these effects are wide and varied. Over the same period, scientific understanding of the effects of pesticides on human health and their mechanisms of action has also expanded rapidly, with studies revealing statistical associations between pesticide exposure and enhanced risks of developmental impairments, neurological and immune disorders and some cancers.

Nevertheless, proving definitively that exposure to a particular pesticide causes a disease or other condition in humans presents a considerable challenge. There are no groups in the human population that are completely unexposed to pesticides, and most diseases are multi-causal giving considerable complexity to public health assessments (Meyer-Baron et al. 2015). Furthermore, most people are exposed to complex and ever changing mixtures of chemicals, not just pesticides, in their daily lives, through multiple routes of exposure. Pesticides contribute further to this toxic burden.

Particularly Exposed or Vulnerable Populations

The general population is exposed to a cocktail of pesticides through the food we consume every day. In agricultural areas in which pesticides are used, these substances drift in the air, pollute the soil and waterways, and are sometimes systemically absorbed by non-target plant species. In cities, spraying of recreational areas also exposes people nearby to a mixture of chemicals. Everyday use of various household pest control substances can also contaminate homes and gardens.

Particularly highly exposed or vulnerable population groups include:

-  Farmers and pesticide applicators, especially greenhouse workers, exposed to high levels of chemicals in their work. This has been clearly shown though levels found in the blood and hair of these workers.

-  The unborn and young children. When women are exposed to pesticides during pregnancy, some of these chemicals pass directly to the developing child in the womb. During development, the fetus is particularly vulnerable to the toxic impacts of pesticides. Young children, in general, are more susceptible than adults due to their increased exposure rates, in that toddlers and crawling babies are more likely to touch surfaces in the home and put their hands in their mouths. Children also have much smaller body sizes than adults and are less able to metabolize toxic substances within their systems.

Widespread Health Impacts

Health impacts that have been reported for children exposed to elevated levels of pesticides in the womb include delayed cognitive development, behavioural effects and birth defects. There is also a strong correlation between pesticide exposure and incidences of childhood leukemia.

Studies have also related higher pesticide exposures to increased incidence of several types of cancer (prostate, lung and others), and neurodegenerative diseases such as Parkinson’s and Alzheimer’s disease. There is also evidence that suggests some pesticides can disrupt normal endocrine function and immune systems in the body. Whilst the mechanisms of such impacts are poorly understood, it is clear that, in some cases, enzyme function and important signaling mechanisms at cellular levels can be disrupted. Studies using DNA-based methods also indicate that certain chemicals disrupt gene expression and this may follow on to generations that are not exposed to pesticides through epigenetic inheritance. This means that the negative impacts of pesticide usage can be extremely long term, even after the substance has been outlawed.

This report examines a growing body of research relating to known, and suspected, human health effects of pesticides. While recognising the inevitable uncertainties and unknowns, and including conflicting and developing research, this review collates and analyses the evidence indicating how industrial agriculture, and the use of synthetic pesticides in particular, is currently undermining the health of farmers and their families, as well as the wider population. Among the many active ingredients that are potentially dangerous to health are the currently approved organophosphates, chlorpyrifos and malathion. Chlorpyrifos is routinely found in food, and in human breast milk, and public health studies indicate strong evidence that it is linked to numerous cancers, impaired development in children, impaired neurological function, Parkinson’s disease and hypersensitivity.

The Solution – Ecological Farming

The only sure approach to reducing our exposure to toxic pesticides is through a move towards a more long-term and sustainable approach to producing food. This will require legally-binding agreements to immediately phase-out all pesticides that are toxic to non-target organisms implemented at both national and international level. Fundamentally changing our approach to farming involves a paradigm shift from industrial agriculture, which relies heavily on chemical additives, towards the full implementation of ecological farming as the only means of feeding the population and protecting the ecosystems we live in. Ecological farming is a modern and effective approach to farming that does not rely on toxic chemicals, and delivers healthy and safe food.