Some 'inerts' cause toxic hazard

In 1997, US agricultural pesticide formulations included about 750 million kg of inert ingredients with a market value of US$388 million(1). New research carried out by the US environmental group the Northwest Coalition for Alternatives to Pesticides (NCAP) reveals how toxic these 'inerts' now appear to be(2).

Despite the fact that 'inert' is synonymous with benign, such is not the case with pesticides. A pesticide inert ingredient is merely any intentionally added substance that is not the active ingredient: 'inert' is not meant to confer safety. The consequence of this is that a member of public may be led to believe that only the active ingredient is of health or environmental concern. In addition, there is much less safety data on inerts in the public domain because of commercial confidentiality concerns of the pesticide industry.
    The US Environmental Protection Agency (EPA), that implements pesticide legislation, has classified many chemicals used as inert ingredients as hazardous. For example, 209 inerts are considered to be hazardous air and water pollutants-14 have been assessed as 'extremely hazardous', 21 are known or suspected carcinogens, and 127 are regarded as occupational hazards.
    Because information about most inert ingredients is not readily available publicly, it is difficult to know how frequently hazardous inerts are used in pesticide products. NCAP has filed a number of requests with the EPA under the Freedom of Information Act to find out how many products contain known or suspected carcinogens, active inerts, and endocrine disrupters, among other health and environmental concerns. Many of the requests are still being processed by the EPA. However, preliminary findings indicate that hazardous inerts are widely used in hundreds or even thousands of products (see table).
    The remedies for these problems are simple according to NCAP. The pesticide product label must contain a complete ingredient statement, one that lists all active ingredients and inert ingredients. Furthermore, the entire pesticide product, which includes active and inert ingredients, must be subjected to all of the toxicological and ecological effects testing required for registration with the EPA. The current testing programme, that involves mostly the active ingredients, fosters a climate of wilful ignorance, according to NCAP.

1. Agricultural additives and adjuvants US IV, Hochberg and Co, PO Box 222, Chester, NJ, 07930, US, Fax +1 908 879 7479.
2. Holly Knight and Caroline Cox, Worst kept Secrets: Toxic inert ingredients in pesticides, Northwest Coalition for Alternatives to Pesticides, PO Box 1393, Eugene, OR 97440, US, available online at www.efn.org/~ncap,9pp.

[This article first appeared in Pesticides News No. 39, March 1998, page 11]