Farmers Reduce Risk of Pesticide Use

The results are in! Farmers have reduced the risk of agricultural pesticide use by 52-60% since 1983

According to the recently released Ontario Ministry of Agriculture, Food, and Rural Affairs (OMAFRA) study "Evaluation of the Changes in Pesticide Risk". Last year we reported that farmers had reduced their pesticide use by 52%, as measured in amount of active ingredient per acre, however we were often asked if this really reduced any potential risk of pesticide use, or were we just using "less volume but more concentrated and toxic stuff".

This study confirms that we have not only reduced the amount of pesticide used, but we've reduced its risk to the environment, farmers, consumers, and non-target species

The OMAFRA study looked at three different measures used to evaluate the potential risk of pesticides to humans and the environment;

The Environmental Impact Quotient (EIQ)
The Environmental Health Index (EHI)
The Priority Substances List (PSL) score.

(The three scoring systems use different methods of calculating potential risk with different results; therefore we are presenting risk measurements as ranges.)

All three scoring systems found that the reduction in risk was greater than the reduction in use, all reporting a reduction in risk per kg of pesticide used.

For fruit production, potential risk was reduced by 53-59% per hectare (ha) and 55-62% per tonne since 1983. Potential risk for vegetable production was reduced by 41-48% per ha and 50-56% per tonne during the same time period. For all field and horticultural crops combined, the average reduction in potential risk was 48-57% per ha and 56-64% per tonne.

The study notes that there was a substantial reduction in pesticide use on fruits and vegetables in 2003, specifically there was a marked reduction in insecticide use in 1998 and 2003 and in fungicide use in 2003.

The Ontario Survey of Pesticide Use has been conducted every five years since 1973. OMAFRA's Food Systems 2002 program began in 1987 with a goal of reducing agricultural pesticide use by 50% of the amount used in 1983. The three main components of the program were:

A mandatory pesticide education program, as requested by farmers (the Grower Pesticide Safety Course)
Hiring of Integrated Pest Management (IPM) staff
Approximately $800,000 per year in research to develop new methods to reduce pesticide use

The primary objective of the "Evaluation of the Changes in Pesticide Risk" study was to assess the risk associated with pesticide use on agricultural crops in Ontario in 2003 to determine if the Food Systems 2002 goal of 50% reduction in agricultural pesticide use was matched by at least a 50% reduction in risk.

There Are Many Reasons Why Farmers Have Been Able to Reduce Both Pesticide Use And Risk

The Food Systems 2002 program itself has had an impact via grower education, IPM programs, and the development of new technologies.

Better crop rotation practices have played a major role, made easier via the introduction of new varieties of soybeans adapted to Ontario's climate that led to a large shift in field crop acreage from corn and grains to soybeans. For example, the 71% reduction in atrazine use and the 97% reduction in insecticide use on corn can be attributed to better crop rotation practices.
The introduction of new technologies has also allowed reduced pesticide use and risk. Several new pesticides are applied at rates of grams per ha instead of kg per ha. Improvements in pesticide application (using electrostatic sprayers, improved sprayer calibration, and banding) have also led to significant reductions.
The introduction of IPM programs, particularly in the fruit and vegetable industries, has also contributed to reductions in both use and risk. The study states that IPM programs can reduce pesticide use on individual crops by 23-61%.
Biotechnology has also played a role. The introduction of Bt corn, which accounted for 32% of the corn planted in the province in 2002, further reduced the need for insecticide use on corn. The use of glyphosate-resistant soybeans appears to have contributed to the reduction in risk because glyphosate has a lower hazard score than other herbicides previously used in larger quantities on conventional soybeans.

What have we learned from Food Systems 2002?

The program, which focussed on grower education, extension, and research, was clearly a success. We continue to see how the combination of education, support, research, and technological advances bring real environmental improvements in agriculture. Farmers respond well to these programs. It's important to note that these improvements were not brought on by regulation.

Congratulations to Ontario's farmers for their ongoing commitment to environmental stewardship!