Montgomery County expands efforts to ban pesticides

Montgomery County (Maryland) Council Vice President George Leventhal is evidently about to introduce legislation to ban the use of certain pesticides on lawns.  The trigger for action is linked to potential health outcomes, specifically those pesticides "classified as carcinogenic or likely to be carcinogenic to humans by the U.S. Environmental Protection Agency."  The bill will also require the County adopt an integrated pest management (IPM) plan. IPM plans are commonly to manage pesticide use and to ensure other (non-chemical) options are exhausted.  

EPA, of course, examines carcinogenicity potential for every pesticide it registers.  The list of compounds evaluated for carcinogenicity through October 2012 has an interesting disclaimer that is worth examining:

How should the information provided in this list be used? 

Although this list is available to the public, note that the list represents only the potential carcinogenicity hazard for the chemical with no consideration of exposure information. This list is not intended to be used independent of the full risk assessment for the chemical. When EPA completes a risk assessment on a pesticide, a variety of toxicity information, including potential for noncancer effects (e.g., neurotoxicity, developmental and reproductive toxicity, 
immunotoxicity, etc) and carcinogenicity, are considered in determining whether to register a pesticide and what requirements for use of the pesticide need to be in place to protect human health. The simple fact of being listed here does not imply that the pesticide poses a significant cancer hazard to the public from use.

Three very important points:

  1. This list does not consider exposure.

  2. This list is not intended to be used outside an individual chemical's full assessment.

  3. Inclusion on the list does not indicate a cancer hazard to the public from use.

That being said, this list identifies just under 50 pesticides that would be triggered.  Oddly enough, about 1/3 of them don't have US registrations, aren't legally approved for use in the US, yet are banned anyway.  Not only has the County (through its municipality Takoma Park, see below) misused the list, but it has done so against the advice of EPA.

Interestingly enough, this is an expansion from past efforts in the County to ban pesticides, where there is currently a ban in Takoma Park on lawn care products on both public and private property. It should be noted that the TP ban contains criteria taken from foreign jurisdictions, rather than from EPA (including a list of potential "endocrine disruptors" from unknown, uncited sources within the European Union).  This approach of incorporating multiple source of "chemical lists" of varying quality and using often non-transparent, non-reproducible methods is poor and fails to recognize exposure as an essential facet of "risk."  There is no risk if there is no exposure, or if the exposure is negligible relative to the levels known to cause adverse health outcomes.  

The TP pesticide ban for residents kicks in January 1, 2015.  This may be in fact the only such County-level pesticide ban on cosmetic uses in the US.  (And not surprising, Maryland is one of a handful of states that allow local governments to enact more stringent pesticide laws.)  

Similar bans have been enacted by several municipalities and provinces in Canada and, in some case, led to the public reacting negatively to unkempt and/or mismanaged public green spaces.  In short, it is unclear that banning use of pesticides in public spaces improves the usability of the space and it is unclear what the public health benefit is (given prior EPA full assessment of each compound that includes the rate at which it is applied).