Poison in Your Park?

It’s a nice, warm, sunny day at the park. True to the weather, you meet up with your friends to have a picnic. Your friend brings a blanket, everyone has food, you lay your head back on the soft, evenly-cut grass, and… what’s that?

You may have just exposed yourself to a carcinogen.

Photo credit: Toxic Free Philly Drexel

Synthetic herbicides, or weed-killers, have a long history of controversy in the climate justice and public health sphere, with cancer liability lawsuits, the argument for and against usage in agriculture, damage to wildlife, and invasive plant control all being points of contention. The ethics of herbicide usage are complicated, to say the least, but one place synthetic herbicides may not be necessary is on parks and campus green spaces for aesthetic purposes. While there is no question that large exposures, such as in the case of accidental downings, proximity to agricultural applications, and counternarcotic aerial sprayings can cause severe health conditions and detrimental effects on wildlife, do lower exposure levels actually matter?

Do lower exposure levels actually matter?

According to a heavily- cited consensus statement published in Environmental Health, current evidence shows that glyphosate, the most widely used herbicide worldwide poses “heightened cancer risk in human populations at levels of exposure actually experienced in human populations,” though more in-vivo studies in low doses are needed to determine the role glyphosate plays in pathological pathways. Despite this gap, knowing that glyphosate has this effect on human health is enough to look for change. The risk glyphosate poses at low doses is especially concerning given that the CDC has found glyphosate or its metabolites in the urine of 80% of Americans tested in their study. Paraquat, another one of the most widely used herbicides, has recently been linked to Parkinson’s disease at long-term low-dose exposures. Among dietary intake, the WHO has IARC listed gardening use and proximity to sprayed areas as the primary routes to glyphosate exposure. The same can be said of other commonly used herbicides. These pathways allow for realistic exposure levels that can compound into silent, yet potentially dangerous consequences down the road.

Are some herbicides better than others?

Image of man spraying herbicidesGlyphosate and paraquat are easily among the most dangerous herbicides. Other commonly used herbicides, including prodiamine, 2,4-D, mecoprop, dicamba, atrazine, and 2,4,5-T are being further evaluated in the scientific community as possible carcinogens and suspected endocrine disruptors. These herbicides are so widespread, it is likely that their names may be familiar to your park or campus grounds. In any case, time and money must be poured into toxicological evaluations for the thousands of herbicide components, and the lack of conclusive studies in human subjects must not be assumed as evidence of safety. Caution should be exercised in chemicals evaluated as possible carcinogens or even those not yet evaluated by sources like the IARC. Besides, in addition to protecting your own health, minimal or absent herbicide usage additionally protects groundskeepers (who have among the highest risk of exposure), wildlife and communities bordering chemical plant emissions. Unlike anti-fungal agents in home insulation or pesticides in furniture, herbicides used for aesthetics and convenience on greenspaces do not serve any protective purpose. While decreasing or eliminating herbicide usage in favor of an organic turf care program- which can actually save water and chemical application costs- is ideal, increasing the safety of our parks also begins with steps like ensuring groundskeepers are trained to use proper protective equipment, applying herbicides in the absence of students or parkgoers present, and directing people away from recently sprayed areas.

Starting out last year with the support of a small group of friends, we began reaching out to administrators on our college campus to gather information about which herbicides were being used on our grounds. Using mindful and non-accusatory language was key in garnering helpful responses. We then started networking with larger organizations focused on herbicide-free advocacy, including Toxic Free Philly and Re:Wild Your Campus (formerly Herbicide Free Campus). These organizations offered guidance and worked with us to create a tangible plan to carry out a potential organic land management transition by involving professional organic land care consultant groups. After proposing such a program to our facilities team under the framework of a research grant in cooperation with faculty, we then struggled through price hurdles for the next several months. During that period, we spend most of our time searching for alternate consultants and applying for grants, a process that our partners at Re:Wild Your Campus helped us through immensely. In the meantime, student fellowship programs with Rachel Carson Council and Re:Wild Your Campus helped us learn more about environmental justice and connected us to other young climate-minded activists. These ideas helped us expand our group to involve more students and new projects aimed at mitigating other environmental toxins. As of today, with the help of supportive campus staff, we believe we are close to beginning the first step in launching the organic transition on our campus.

Changing campus beautification culture is still among the more difficult steps in our goal. While having an aesthetically pleasing campus may be a significant factor in collegiate status and student life, our turf does not need to be pristine and spotless to attract new undergraduate students (not that these results haven’t been proven possible with a rigorous organic program). In fact, many weeds can serve as important pollinators that contribute to the campus ecosystem. To gain traction in our movement, we need to emphasize that weeds are not necessarily an aesthetic killer. By showing our campus administration that to students, caution in the usage of potentially carcinogen chemicals is higher on the priority list compared to fewer weeds on campus, we can facilitate this change.

In a world where exposure to carcinogens is almost impossible to avoid- from microplastics in the food we eat to benzene in the air we breathe, it may become easy to start expecting their routine presence. But we need to remain on alert and continue due diligence in scrutinizing cosmetic chemical usage in our parks and on our campuses.

Kacy Gao, Sean Vanson


RCC Fellow –Kacy Gao – Drexel University

RCC Fellow Kacy Gao is a Biological Sciences major and Chemistry minor at Drexel University with an interest in environmental health. Having seen the disproportionate impact environmental toxin exposure has on low-income communities through community dialogue and EMS, her goal is oriented advocating for change through policy and activism. She is currently leading a campaign on campus to transition from the use of toxic synthetic herbicides to organic land management, as well as an effort to enforce a similar law in the city of Philadelphia.

RCC Fellow – Sean Vanson – Drexel University

RCC Fellow Sean Vanson is a sophomore at Drexel University in the honors program majoring in Biological Sciences. Originally from Wilmington, Delaware, he is passionate about promoting environmental justice on his campus and his local community in Philadelphia, with emphasis on eliminating the use of toxic synthetic herbicides. After completing his undergraduate education, Sean hopes to attend medical school and obtain a medical degree related to environmental medicine.


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