On a quarter acre lot, about half of the area would be grass and shrubs and would be treated. The number of ounces of pesticide applied to a yard would depend on the concentration of the pesticide in the formulation, but when applied at the above rate, a square yard of turf or other surface would have maximum pesticide residues of 0.0033 ounces. Incidental ingestion, inhalation, or skin contact with the diluted spray does not usually cause harm. However, a misapplication or overdose could result in illness. One should avoid direct contact with the eyes or prolonged skin exposure.
Skin contact is the most likely exposure route.
The first effects of airborne OP overexposure are breathing and eye symptoms. Although unlikely to occur, cholinesterase inhibition from OP exposure is possible. Cholinesterase inhibition, a disruption of normal nervous system function, is characterized by symptoms such as headache, nausea, and dizziness. An individual can have a cholinesterase level check done by a physician to confirm exposure or toxicity. Diazinon does not cause cancer, nerve damage, or reproductive problems.