(Beyond Pesticides, October 3, 2013) According to new research, residents are more highly exposed to organophosphate and pyrethroid pesticides in New York City (NYC) than in the U.S. overall. Researchers from the city’s Department of Health and Mental Hygiene reviewed the 2004 NYC Health and Nutrition Examination Survey (NYC HANES) to compare its pesticide exposure patterns in an urban environment with the nation as a whole. The NYC HANES includes a biomonitoring component to evaluate pesticide exposures by measuring concentrations of organophosphate and pyrethroid metabolites in urine. According to the authors, the findings underscore the importance of considering pest and pesticide burdens on cities, where a dense population results in a single exposure source affecting many people at the same time when regulating pesticide use.
Organophosphate metabolites were measured in the urine of 882 New Yorkers, while 1,452 residents were tested for pyrethroid metabolites. As the researchers explain, the building density and disrepair in parts of NYC likely increased the chances of a pest infestation, which in turn can lead to the reliance on indoor pesticide use. By the 1980’s, organophosphates were the most common class of insecticides in the U.S., and were used indoors until the early 2000’s when structural pest control operators shifted toward the use of pyrethroid products. Some organophosphates have been banned for residential use the U.S. in recent years, although many are still heavily used in agriculture. Both chemical classes work by disrupting the insect’s nervous system. Organophosphates inhibit cholinesterase, a neurotransmitter that carries signals between nerves and muscles. Inhibiting cholinesterase can cause poisoning victims to suffocate due to paralysis and cause lungs to fill up with fluid. Children are at an elevated risk for organophosphate pesticide poisoning. A 2012 study that pulled data from 14 studies over the past 20 years found that long-term low-dose exposure to organophosphates can damage neurological and cognitive functions. Other studies have also connected low-dose exposure to organophosphates to ADHD, reduced IQs, and Alzheimers. Previous research has already suggested that pesticides, particularly organophosphates, cause a variety of serious neurological health problems, including Parkinson’s disease. This is not surprising, as organophosphates are known to be extremely toxic to nerve cells and deadly at large doses. Recently, organophosphate pesticides caused the deaths of 25 children in India from contaminated school lunches.
Among New Yorkers who were 20 to 59 years old in 2004, the highest exposed group had between two and six times more organophosphates in their urine than the highest exposed group in a national study. They also had between 1.7 and 2.4 times more pyrethroids than the nationwide group. Researchers also sought to identify some of the demographic and cultural characteristics that predict the higher exposures. They found that overall, Hispanics and blacks, older residents, and people who had pesticides professionally applied recently in their home had higher levels of organophosphates. Interestingly, the researchers also find that those who ate one or more pieces of fruit every day were more likely to have higher levels of organophosphates. These factors are not necessarily linked, and researchers found no published evidence that more frequent fruit consumption in NYC might explain higher exposure than the rest of the U.S. However, the researchers do point out that metabolites they found in urine are derived from pesticides that are the most commonly used in agriculture, and that residues from this class of active ingredients are detected in 41% of apple, pear and strawberry samples measured by the U.S. Department of Agriculture (USDA) Pesticide Data Program in 2004. For pyrethroids, there were no major differences between the races or ages, suggesting widespread exposure. People who ate green vegetables had higher levels but the researchers said the differences “are relatively small and not likely to be biologically meaningful.”
With the phase-out of most residential uses of the common organophosphate insecticides, home use of pyrethroids has increased. These chemicals are widely used around the home for various insects and mosquito control as well as in agricultural settings. This class of chemicals includes permethrin, bifenthrin, resmethrin, cyfluthrin and scores of others. Pesticide products containing synthetic pyrethroids are often described by pest control operators and community mosquito management bureaus as “safe as chrysanthemum flowers.” While pyrethroids are a synthetic version of an extract from the chyrsanthemum plant, they are chemically engineered to be more toxic, take longer to break down, and are often formulated with synergists, increasing potency, and compromising the human body’s ability to detoxify the pesticide.
Pyrethriods are known irritants and can have a high acute toxicity depending on the specific formulation. Pyrethriods have also been connected to multiple symptoms of acute toxicity, asthma, incoordination, tremors, and convulsions. In addition to human health effects, which this cumulative risk assessment addresses, pyrethroids are also persistent in the environment and adversely impact non-target organisms. A 2008 survey found pyrethroid contamination in 100 percent of urban streams sampled in California. Researchers also find pyrethroid residues in California streams at relatively low concentrations (10-20 parts per trillion) in river and creek sediments that are toxic to bottom dwelling fish. Other studies find pyrethroids present in effluent from sewage treatment plants at concentrations just high enough to be toxic to sensitive aquatic organisms.
Fortunately, the authors point out, since the 2004 NYC HANES was conducted, the NYC Health Department has taken several steps to try and reduce pesticide exposure by restricting the use of certain pesticides on city property, and promote Integrated Pest Management. The state of New York has also taken actions in recent years to protect its citizens and the environment from nutrient pollution and exposure to toxic pesticides. In 2010, the state of New York passed the Child Safe Playing Field Act, which requires that all schools, preschools, and day care centers both public and private stop using pesticides on any playgrounds or playing fields. The bill allows pesticides to be used for infestations only if the County Health Department, the Commissioner of Health, the Commissioner of Environmental Conservation or the school board deems it an emergency.
There are clear established methods for managing homes that prevent infestation of unwanted insects without the use of synthetic chemicals, including exclusion techniques, sanitation and maintenance practices, as well as mechanical and least-toxic controls (which include boric acid and diatomaceous earth). Based on range of successful pest prevention practices, use of these hazardous chemicals are unnecessary.
Most people are unaware that they carry chemical compounds in their bodies. Chemical ‘body burden’ refers to the accumulation of synthetic chemicals found in pesticides, cosmetics, industrial solvents, heavy metals in our bodies. For more information, see Beyond Pesticides’ Body Burden entry in the Pesticide Induced Diseases Database (PIDD).
The full article, “Population-Based Biomonitoring of Exposure to Organophosphate and Pyrethroid Pesticides in New York City” is available from Environmental Health Perspectives.
Source: Environmental Health News
All unattributed positions and opinions in this piece are those of Beyond Pesticides.