Which of the following is NOT a method of reducing toxicant exposure?

Overlapping shift work is not a method of reducing toxicant exposure. Instead, it could potentially increase exposure risks. Employees working extended hours or in overlapping shifts may be subjected to hazardous environments for longer periods, which can lead to cumulative exposure to toxicants.

In contrast, the other methods listed are actively designed to mitigate exposure. Substitution with less harmful chemicals decreases the risks associated with using more toxic substances. Improving ventilation systems helps to reduce airborne toxicants by enhancing air circulation and quality in a work environment. Implementing strict safety protocols directly addresses safety measures that help to ensure workers are less likely to come into contact with or be harmed by hazardous materials. Each of these methods contributes positively to maintaining a safer workplace and minimizing the risk of toxic exposure.