Dow AgroSciences Analysis
As chlorpyrifos is subjected to the EPA’s stringent review and reregistration process, critics and supporters alike will have opportunities to voice their views and influence the EPA’s decision. (See our Registration Review pages on this site.) Rather than leave public interpretation of the wealth of studies conducted on chlorpyrifos to sensationalism and misinformation, we want to offer those seeking a more balanced perspective a better understanding of the product’s regulation and the safety standards governing its use.
To this end, we’ve provided here summaries of chlorpyrifos research with our analysis of the studies most often cited by opposition groups. Following the summaries are links to PDF's of more detailed papers.
Read synopses of independent reviews.
The Insecticide Chlorpyrifos: How Standards are Set for the Protection of Human Health
How are pesticide exposure limits set? Do those limits provide reasonable protection for human health? When controversy arises, how do we know which scientific studies to believe?
This paper answers these questions by providing a high-level overview of the EPA’s current process for determining chlorpyrifos exposure limits
and the science behind chlorpyrifos studies. It also suggests ways of understanding those studies from the perspective of an informed reader — because not all of the science out there is relevant, valid, or reliable.
Evolving regulatory policies along with the availability of the new data and new ways of reducing uncertainty in interpreting that data are shaping the future of determining exposure limits.
Chlorpyrifos Studies: The Debate is in the Details
More than 5,000 research studies have been conducted on chlorpyrifos over a span of decades. Some of these studies have been used by chlorpyrifos’ critics as evidence to make allegations about potential dangers of chlorpyrifos exposure. While some of these studies have been well-conducted, many of them pursue subtle effects where proper interpretation is a significant challenge.
This paper provides a detailed analysis of some of the most controversial scientific studies involving chlorpyrifos. It highlights the problems inherent in these studies’ design and execution and provides perspective on their relative value to assessing risk when judged against decades of research on chlorpyrifos.
We also provide summaries of the studies discussed in the longer paper.
Limitations of the Columbia University Study of Birth Weight and Childhood Development
Researchers at Columbia University reported that exposure to chlorpyrifos prior to birth can be linked to decreased body length and weight at birth and to later childhood developmental issues. The study measured exposure to chlorpyrifos in terms of its presence in umbilical cord blood at birth. At face value, the Columbia University research raises serious questions, and further research into this area will most certainly be conducted. There are compelling reasons, however, why the reported outcomes of these papers are not likely to have been caused by chlorpyrifos. This paper focuses on the limitations of the Columbia study;linking chlorpyrifos exposure to birth weight and childhood development issues.
