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Laws Governing Drift

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The following information can be found in more detail in "Secondhand Pesticides: Airborne Pesticide Drift in California." See Resources. This report is also available in PDF. Updates to this page reflect changes in legal issues related to drift since the report was released in 2003.

Present and proposed regulatory strategies do not protect public health and the environment

Most people who are made ill or whose property is contaminated or made unusable by other people's pesticide use have less protection and recourse under the law than someone whose property is defaced with paint. In light of the illness, economic loss, and ecosystem disruption associated with pesticide drift, major changes must be made in the laws and regulations related to pesticide drift in order to protect public health and the environment.

Spray drift, which is drift that occurs during pesticide applications, is poorly regulated by current state and federal laws and regulations. Post-application drift, which can occur for many days after an application, is barely regulated at all and is not acknowledged by U.S. EPA as a source of exposure except for the case of fumigant pesticides and mosquito fogging agents. Even then, protection measures to reduce exposures are in place only for a single fumigant pesticide, 1,3-dichloropropene (Telone).

Inadequate enforcement compounds the problem, making it easy for pesticide applicators to be careless with applications with little threat of punishment for violations. However, not all problems from drift are a result of illegal applications. Drift that occurs when applications are conducted in accordance with the label law also cause problems. Here is where changes in laws and regulations are most needed.

The U.S. EPA and other state agencies have the authority to regulate drift, with U.S. EPA policies setting the regulatory "floor" for states. States are authorized to create more stringent regulations if they wish. California has done so with respect to drift, and is somewhat ahead of most other states in this regard. However, even in California, regulations have not been successful in preventing acute poisonings or long-term exposures that exceed levels of concern. Thus, federal and state regulations around pesticide drift largely fail to protect human health and the environment.

Regulatory Definition of Drift Ignores 80-95% of Total Drift for Volatile Pesticides

The most obvious flaw in both U.S. EPA and state regulatory processes for drift control is failure to define pesticide drift to include all forms of drift. U.S. EPA currently defines drift as the airborne, offsite movement of pesticides that occurs during and immediately after application. Yet PANNA's detailed analysis of monitoring data shows that, for volatile pesticides, the bulk of off-site movement occurs as pesticides volatilize after application (see figures below and in Secondhand Pesticides, Figure 3-1).

Such post-application drift usually peaks between 8 and 24 hours after the start of application, and can persist for many days above levels of concern (see Secondhand Pesticides, Chapter 2). The California Air Resources Board monitoring data show that, for most of the volatile pesticides, post-application drift typically accounts for 80-95% of the total off-site, airborne movement of pesticides. Approximately 45% of reported pesticide use during the year 2000 in California (where data are available) fell into the category of volatile pesticides, or about 84 million pounds.

Controls during the time of a pesticide application are necessary to reduce application-related spray drift, but such measures will not control post-application drift of volatile pesticides. In order to address the adverse effects caused by pesticide drift, post-application drift must be regulated as well as spray drift. The most effective approach would be to phase out or reduce use of the most dangerous drift-prone pesticides.

Spray-drift controls are ineffective

U.S. EPA label restrictions do not solve the problem

U.S. EPA has a responsibility for regulating spray drift through requirements and instructions written on the pesticide label. Labels currently may present one or more broad statements such as "Do not allow pesticide to drift," "Do not allow pesticide to contaminate persons not involved in the application," or "Do not apply pesticide when environmental conditions favor drift." A growing number of labels also specify allowable application equipment, spray droplet size, and weather conditions for application, such as "Do not apply when wind speeds exceed 10 mph." Many labels have no statement prohibiting drift, other than the worker protection statement that prohibits drift from contacting workers. Interestingly, labels on the most drift-prone pesticides-- fumigants--carry none of these prohibitions. The only fumigant with any U.S. EPA-mandated drift risk prevention measures on the label is 1,3-dichloropropene, which requires a 100-300 foot buffer zone.

Even when label language specifies "no drift," the reality is quite different. The experiences of many whose yards, homes, cars, pets, livestock, and even their own bodies have been contaminated show that there are continuous, serious problems with spray drift.

California Spray Drift Regulations

California laws and regulations on spray drift are more extensive than the federal U.S. EPA requirements, but still lack the clarity needed in order for effective enforcement to take place. In addition to the federal label requirements, California law says that pesticides must be applied in a manner that prevents "substantial drift." Substantial drift is defined in regulations as when "the quantity of pesticide outside of the area treated is greater than that which would have resulted had the applicator used due care." The regulations do not say what is meant by "due care", but they do state that no pesticide application should be made or continued if there is possibility of:

  • Any contamination of people not involved in the application process; or
  • Damage to non-target crops, animals, or other public or private property; or
  • Contamination of non-target property, including creation of a health hazard preventing normal use of such property. In determining a health hazard, the amount and toxicity of the pesticide, the type and uses of the property, and related factors should be considered.

The law also states that "No person shall directly discharge a pesticide onto a property without the consent of the owner or operator of the property."

For a few specific herbicides and cotton defoliants, current California regulations include spray-drift controls meant to prevent damage to non-target crops. These controls include guidelines around minimum and maximum wind speeds during application, allowable application equipment, and buffer zones. New methyl bromide soil fumigation regulations include buffer zones and restrictions on when the pesticide can be applied close to schools. The state has recommended conditions for other soil fumigants as well (see Secondhand Pesticides, page 49), which counties may enforce at their own discretion. Some counties have additional requirements for pesticide use near schools, residential areas, or other sensitive sites (see Secondhand Pesticides, Table 3-1). However, these conditions usually apply only to "restricted use" pesticides, a small subset of the total amount of pesticides used.

Regulation of Post-Application Drift in California

Although U.S. EPA has only just begun to consider exposures from post-application drift, the state of California has recognized pesticides as an air toxics problem for many years. In 1983, the California legislature passed the Toxic Air Contaminant (TAC) Act to protect public health from toxic airborne pollutants, including pesticides. This law, if properly implemented and enforced, could do a tremendous amount to reduce the dangers posed to human health by toxic post-application drift.

TAC law requires the California Department of Pesticide Regulation (DPR) to:

  1. Prioritize a list of pesticides for "TAC status" - pesticides that post the greatest threat to the contamination of air,
  2. Estimate the potential for human exposure to such pesticides by working with the California Air Resources Board (ARB) to conduct air monitoring
  3. Evaluate the health effects of these chemicals in air, and
  4. Reduce exposures to such chemicals to levels "at which no significant adverse health effects are anticipated."

The law established an external Scientific Review Panel and requires DPR to submit all information about exposures and health effects to the Panel for review. The California Office of Environmental Health Hazard Assessment is also required to be a part of this process, reviewing pesticide toxicology and making recommendations to DPR. The law provides an opportunity for public review and comment as well.

Pesticides that fit the TAC definition--an air pollutant that "may be emitted to the ambient air" . . which may cause or contribute to an increase in mortality or an increase in serious illness, or which may pose a present or potential hazard to human health" --must be listed as TAC chemicals. It is then DPR's job to determine the control measures needed to reduce emissions and protect the public.

The TAC process has moved at snail's pace for pesticides. Over the past 19 years, two California state agencies, the Air Resources Board (ARB) and the Office of Environmental Health Hazard Assessment (OEHHA), have listed over 22 chemicals as TACs and adopted an additional ~180 chemicals from the U.S. EPA Hazardous Air Pollutant (HAP) list as TACs. During the same time, DPR listed only four pesticides as TACs, and has done draft evaluations for only three others, while adopting approximately 35 pesticides from the U.S. EPA's HAP list as TACs. And although DPR has named approximately 200 pesticides with the potential to be listed as TACs, it has not created an adquate way to ensure that the most drift-prone and hazardous chemicals be evaluated first. In 2002, DPR withdrew three harmful pesticides, molinate, chlorpyrifos, and azinphos methyl, from further review based on DPR’s internal findings without the input of other agencies, the scientific review board, or the public. DPR then modified the process through which pesticides are selected for risk assessment in 2004, removing itself further from public and institutional oversight and failing to follow the mandate of the TAC law by not using the TAC criteria to prioritize chemicals for risk assessment.

The final step in the TAC process requires the Department of Pesticide Regulation to reduce risk of exposure to TACs. Currently, only one TAC pesticide (ethyl parathion) has been removed from the market, mostly because of the high risk of worker poisoning. For the most recently listed TACs, DPR stated that it plans to regulate only exposures that cause short-term symptoms of poisoning and will not take into account the health effects of longer-term and/or lower level exposures, thus ensuring its actions will fall short of adequately protecting public and worker health (see Secondhand Pesticides, page 50). As of fall 2006, ARB and OEHHA have taken action on a number of non-pesticide TACs to reduce exposures, but DPR has yet to take action on a single chemical under the TAC statute to reduce exposure and mitigate harm.

DPR has begun the process of increasing restrictions for only a single pesticide--methyl bromide--and then only because the agency has been repeatedly sued for inaction regarding this poisonous fumigant pesticide (see Secondhand Pesticides, page 49). For another major-use pesticide, 1,3-dichloropropene, DPR has changed conditions of use to allow more use with fewer restrictions since 1995, instead of imposing greater restrictions on use (see Secondhand Pesticides, page 51).

In January of 2005, PANNA, Californians for Pesticide Reform, Wishtoyo Foundation/Ventura CoastKeeper, Grayson Neighborhood Council, Association of Irritated Residents, and Children's and Community Advocates Against Pesticide Poisoning filed suit against DPR for failure to implement the TAC statute. Download the opening brief here. The suit makes three claims: 1) The first claim requested the Court to declare that DPR’s new risk assessment policy is contrary to the TAC law and to rule that DPR has failed to implement the law. The new policy allows DPR to avoid external scientific review of their assessment of the health risks posed by airborne pesticides, resulting in DPR making its own unilateral decisions without necessarily using the best available science. 2) The second claim requested the Court to order DPR to implement the TAC statute, by initiating review of specific pesticides on a reasonable schedule. 3) The third claim requested the Court to set aside DPR’s new risk assessment policy as illegal because the policy was created without going through the official rule-making process.

In February 2006, the judge ruled against PANNA et al. in favor of DPR. In denying PANNA's claims, the trial court found that DPR’s new risk assessment policy was a “prioritization” process and thus a permissible exercise of DPR’s discretion to determine the order in which pesticides would undergo TAC review. An appeal of this decision was filed in August 2006. Download the appeal here.

Regulation of Pesticide VOCs under the Federal Clean Air Act

Many pesticides and/or the other ingredients they are mixed with also have significant impacts on air quality because they are Volatile Organic Compounds (VOCs), air pollutants that mix with other air pollutants and react in sunlight to form ground-level ozone, an ingredient of smog known to cause and exacerbate asthma and other respiratory diseases. The Federal Clean Air Act requires action to reduce VOCs to bring regions into compliance with the federal ozone standard.

In California, several community groups (Center on Race, Poverty and the Environment, Wishtoyo Foundation/Ventura CoastKeeper, and El Comite para el Bienestar de Earlimart) filed suit in January 2005 against the California Department of Pesticide Regulation (DPR) for failing to implement the Pesticide State Implementation Plan required by the Federal Clean Air Act for ozone non-attainment areas. As a result of the suit, the court recently ordered California to reduce such smog forming emissions from pesticides, a significant environmental victory for all Californians. DPR appealed the decision, but has started the process of taking action to reduce pesticide VOCs by announcing the Pesticide Air Quality Initiative. DPR's plans to reduce VOCs include:

  • Reducing emissions from fumigants;
  • Reformulating other pesticide products to reduce emissions;
  • Promoting new, more environmentally-friendly technologies, and
  • Developing strategic pest management partnerships in concert with industry

Resources

Volatile Organic Compound (VOC) Emissions from Pesticides, California Department of Pesticide Regulation.

See the complete list of resources about pesticide drift.

‹ What to Do if You Have Been Drifted OnupPesticide Contributions to the Ozone Problem in California ›

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