Cancer Risk From Pesticides Comparable To Smoking For Some Cancers

Food security comes with a steep price: the strongest associations between pesticides and cancer was for non-Hodgkin’s lymphoma, leukaemia, and bladder cancer

Modern agriculture currently feeds the burgeoning human population mainly because of the widespread use of pesticides. Although these chemicals appear to be miracles for agriculture and food security, pesticide exposure harms the health of plants, animals and humans, according to an alarming, but not especially surprising, new study (ref). This study compared the increased risk of cancers due to pesticide exposure to smoking, a noxious habit that is associated with a much better understood cancer risk.

“In our study we found that for some cancers, the effect of agricultural pesticide usage is comparable in magnitude to the effect of smoking,” said the study’s senior author, Isain Zapata, an Assistant Professor of Research and Statistics at Rocky Vista University, a private for-profit medical school in Colorado.

Unfortunately, farmers and farm workers are not the only groups faced with this increased risk of cancers. People who live downwind or nearby are also at risk.

“We accept that a person who is not a farmer living in a community with heavy agricultural production is exposed to many of the pesticides used in their vicinity,” Professor Zapata remarked. “It becomes part of their environment.”

Professor Zapata and collaborators found that simply living near farms was enough to increase a person’s risk of cancers and in some cases, that increased cancer risk surpassed cancers caused by smoking. The strongest cancer risks were for non-Hodgkin’s lymphoma, leukaemia, and bladder cancer (Figure 2). Most disturbing was the finding that cancer risks due to pesticide exposures were actually higher for these particular forms of cancer than due to the risks from smoking.

Are one or two pesticides more dangerous than all the others?

“We present a list of major pesticide contributors for some specific cancers, but we highlight strongly that it is the combination of all of them and not just a single one that matters,” Professor Zapata explained. This list names 69 different agricultural pesticides for which use data are publicly available from the United States Geological Survey.

But these pesticides aren’t used used at a time. Instead, they are applied as pesticide “cocktails”, and thus, it is unlikely that just one or a few are to blame.

“In the real world, it is not likely that people are exposed to a single pesticide, but more to a cocktail of pesticides within their region,” Professor Zapata cautioned.

This study is the first comprehensive examination of cancer risks due to pesticide exposures with a population-based perspective at a national level, according to Professor Zapata and collaborators. Further, this is the first time that cancer risks due to pesticide exposures have been placed into a context with a cancer risk factor that is no longer questioned, in this case smoking.

“It is difficult to explain the magnitude of an issue without presenting any context, so we incorporated smoking data,” Professor Zapata explained. “We were surprised to see estimates in similar ranges.”

Professor Zapata and collaborators pointed out that cancer risk factors are complicated and so-called big picture assessments may not reflect individual outcomes. For example, they found that geography had a strong impact on cancer.

In regions where more crops are grown, such as the Midwest, where corn is king, the associations between pesticides and cancer incidence were more striking and concerning.

One of the goals that Professor Zapata and collaborators have is to motivate people, especially those who are not frequently confronted with pesticide use, to consider the problems that widespread pesticide use poses within the bigger context.

“Every time I go to the supermarket to buy food, I think of a farmer who was part of making that product. These people often put themselves at risk for my convenience and that plays a role in my appreciation for that product,” Professor Zapata explained. “It definitely has had an impact on how I feel when that forgotten tomato in the fridge goes bad and I have to put it in the trash.”

Source:

Jacob Gerken, Gear Thomas Vincent, Demi Zapata, Ileana G. Barron, and Isain Zapata (2024). Comprehensive assessment of pesticide use patterns and increased cancer risk, Frontiers in Cancer Control and Society 2 | doi:10.3389/fcacs.2024.1368086