By Andrea Golaine Case, M.S.
Posted: Saturday, April 1, 1995

ARTICLES
Publication Date: April 1, 1995

For years, environmental magazines like Audubon, Sierra and National Wildlife have been exaggerating the health and environmental risks of golf-course pesticide use. Recent studies associating pesticides with cancer led radio commentator Paul Harvey (who otherwise has an almost impeccable record in reporting accurately on science) to charge that pesticides applied to golf courses "might be killing people." In short, the green specter of toxic terror on the golf course has been brought to the fore once again. But as you head out to the links this weekend, you should take a healthy dose of skepticism and common sense along with your clubs.

While manicured greens and rolling lawns are not exactly virgin land, neither are they the Western equivalent of Eastern-block industrial sites. A well-designed, beautifully maintained golf course gives aesthetic pleasure, provides a habitat for animals and offers recreational and economic opportunities. Pesticides are necessary for the maintenance of a golf course's lush greenery and smooth playing surfaces. Pesticides also reduce allergenic pollen levels and keep the course relatively insect free, protecting golfers from mosquitoes and the ticks that carry Lyme disease.

Ensuring Pesticide Safety

Paul Harvey commented that "the modern golf course, with its 'perfect fairways and pretty flowers at any price,' is a living laboratory," thus suggesting that the humans out on the greens are just guinea pigs. He also quoted Environmental Protection Agency (EPA) personnel as saying that no pesticide is safe.

That statement should come as no surprise, of course: Pesticides, by definition, kill pests. Insecticides kill insects, fungicides kill fungi and herbicides kill weeds. It is a serious error, however, to assume that because pesticides kill pests they are necessarily a threat to nontargeted wildlife or to humans. The hazard presented by any given pesticide depends on both the inherent toxicity of the substance and the dose: A dose of insecticide that is generally lethal to tiny insects will present little hazard to larger animals or to humans. Furthermore, many pesticides and herbicides are relatively specific in their toxic effects. Under conditions of normal use, for example, phenoxy herbicides kill most broadleaf plants but do not adversely affect grasses, insects or rodents.

Under the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA), the EPA registers all new pesticides. A strictly defined system controls the development, distribution, promotion, handling, storage, use and disposal of pesticides. Before registering a pesticide, a manufacturer is required to do up to 120 different tests for toxicity and carcinogenicity.

Using the results of those tests, the EPA balances the risks of pesticide exposure to humans and the environment against the benefits of the pesticide to society. If the benefits outweigh the risks, the pesticide is approved along with strict rules on how and when it can be used. Some pesticides are approved for general use; others must be applied only by professionals trained to handle and use them safely. This extensive regulatory system ensures that pesticides, when used according to the label directions, will not pose unreasonable risks to human health or the environment.

Golf-course maintenance is carried out by professionals who adhere to the strict, federally mandated guidelines establishing safe pesticide use. Course employees and contractors are required to document all pesticide use and must adhere to reentry periods after chemical applications. All these factors reduce the chance that golfers or bystanders will be exposed to even trace pesticide residues.

Allergic Reactions and Other Acute Hazards

The most frightening indictment of golf-course health hazards occurred in the early 1980s, when a 30-year-old Navy lieutenant named George Prior became ill after playing golf over a Labor Day weekend in Arlington, Virginia.

According to an article in the July/August 1993 issue of Sierra, the year was 1983. After playing a few rounds, Prior "experienced headaches, fever and nausea. Within three days a sunburn-like rash covered his body, and large blisters hung from his arms and back. He developed pneumonia and kidney failure, fell into a coma, and died some 20 days after the game," allegedly from "a violent allergic reaction to one of golf's most common pesticides, chlorothalonil."

According to a November 1987 Audubon article, however, the year of Prior's death was 1982; and while the reports of a rash and blisters were consistent, this article reported that "Prior died of a heart attack."

In the hospital, doctors diagnosed Prior with toxic epidermal necrolysis (TEN), a serious disease with symptoms resembling a second-degree burn. About 20 percent of TEN patients die from the disease; in cases of sudden, spontaneous origin, the mortality rate is 50 percent. Bacterial infections and severe reactions to antibiotics had been associated with cases of TEN, but pesticide allergy had not previously been suggested as a cause of the disease. The label on the pesticide Daconil 2787 (chlorothalonil) notes that the product may "produce temporary allergic effects" in applicators, but the lieutenant's illness was far more severe.

Allergies can be dangerous, and rare allergies to certain pesticides do exist — as do allergies to strawberries or bee stings. Since 1982, however, there have been no other deaths associated with golf-course pesticide use. Tens of millions of golfers have played on treated courses and have suffered no ill effects.

Chronic Hazards?

If acute hazards — hazards resulting from a single exposure to a pesticide — are rare on the golf course, what about chronic hazards resulting from repeated low-level exposures over time? Is an avid golfer who spends every weekend on the fairways at risk of disease from long-term exposure?

Beyond the EPA's required tests for toxicity and carcinogenicity, epidemiological studies have followed pesticide manufacturing workers and pesticide applicators over time. By and large, the studies have found no significant links to cancer. If no reliable associations have been found among workers and applicators — who have higher and more frequent exposures to pesticides than regular golf players or even golf pros — these latter groups can rest assured that they are not at risk.

A series of case reports and case-control studies (studies that try to determine the past exposures of current cancer cases and compare them to those of control subjects) in the late 1970s and early 1980s suggested an association between phenoxy herbicides such as 2,4-dichlorophenoxyacetic acid (2,4-D) and two diverse groups of cancers: soft-tissue sarcomas (STS) and non-Hodgkin's lymphomas (NHL). These early studies were controversial because of suspected methodological problems.

Subsequent epidemiological studies (including studies that followed workers for up to 30 years after a known exposure rather than just estimating past exposure after a diagnosis of disease) do not support a link between the herbicides and STS. The evidence regarding NHL is equivocal. Studies of workers who manufactured phenoxy herbicides suggest that the risk, if it exists at all, is small. The National Cancer Institute has noted that occasional use or bystander exposure — in contrast with the exposure of a manufacturing worker or applicator — has not been associated with an increased risk of NHL.

Another series of studies, this time regarding the home use of pesticides and their relationship to childhood cancers, was featured in Paul Harvey's commentary on chemical risks on the golf course. The exposures described in these studies (from the American Journal of Public Health [AJPH]) are not necessarily comparable to golf course exposures: The types and amounts of chemicals used vary, and the application of pesticides in the home is not generally carried out by professionals, as is the case with golf-course applications. These studies, rather than confirm any true hazard from pesticide exposure, instead present another line of evidence that is indeterminate at worst and provides no evidence of a significant hazard.

The latest of these studies, by Drs. Jack Leiss and David Savitz reported in the February 1995 issue of the AJPH, investigated links of pesticides to leukemias, brain tumors, lymphomas and soft-tissue sarcomas. It identified virtually no significant associations between pesticide exposures and cancers. Regarding yard treatments specifically, the study found only one mildly significant association with STS out of many tested (remember that STS was not associated with pesticide exposure in numerous worker studies). Leiss and Savitz's data did not support an association between yard treatments and childhood lymphomas, the type of cancer for which the evidence is still equivocal in studies of adult workers and applicators.

The authors themselves acknowledge that their exposure measures were crude and that their results may be hindered by recall bias (parents whose children have cancer may better remember using pesticides in their home in the past). None of these factors, however, kept Paul Harvey or USA Today from publicizing the Leiss and Savitz results in a hysterical way.

Head Out to the Fairways with Confidence

Environmental alarmists want to reduce or eliminate the use of pesticides, and media types looking for a dramatic story willingly help the alarmists convince the public that pesticides pose an unacceptable risk. In that context, golf-course pesticide use is a prime target; for unlike the use of these chemicals for crop protection or disease eradication, pesticides use to allow golfers to hit little white balls in beautiful surroundings may be seen as unnecessary. Indeed, under a regulatory scheme that balances the risks and benefits of pesticide use, some critics deem golf-course maintenance unjustified.

But evidence proving any human health hazard from the regulated use of pesticides on golf courses is lacking. Twenty-seven million Americans currently play golf, and that number is growing. As they head for the links, they need not be concerned about hypothetical health hazards on the lush — and healthy — greens.

Parts of this article were adapted from ACSH's booklet Lawn Care Chemicals (1992).

Andrea Golaine Case, M.S., is Research Director for the American Council on Science and Health.

(From Priorities Vol. 7, No. 2, 1995)