A worker not exposed to a neurotoxic substance will never develop any adverse neurotoxic health effects from that substance. Zero exposure leads to total protection against neurotoxic health effects. This is the essence of all primary prevention measures.
Toxicity Testing
New chemical compounds introduced into the workplace and in occupational settings should have already been tested for neurotoxicity. Failure to do pre-market toxicity testing can lead to workers’ contact and potentially severe adverse health effects. The introduction of methyl n-butyl ketone into a workplace in the United States is a classic example of the possible hazards of untested neurotoxicants being introduced into the workplace (Spencer and Schaumburg 1980).
Engineering Controls
Engineering controls (e.g., ventilation systems, closed production facilities) are the best means for keeping workers’ exposures below permissible exposure limits. Closed chemical processes that keep all toxicants from being released into the workplace environment are the ideal. If this is not possible, closed ventilation systems that exhaust ambient air vapours and are designed so as to pull contaminated air away from workers are useful when well designed, adequately maintained, and properly operated.
Personal Protection Equipment
In situations where engineering controls are unavailable to reduce workers’ contact with neurotoxicants, personal protective equipment must be provided. Because workplace neurotoxicants are many, and routes of exposure differ across workplaces and work conditions, the kind of personal protective equipment must be carefully selected for the situation at hand. For example, the neurotoxicant lead can exert its toxicity when lead-laden dust is breathed and when lead particles are ingested in food or water. Therefore, personal protective equipment must protect against both routes of exposure. This would mean respiratory protection equipment and adoption of personal hygiene measures to prevent consumption of lead-contaminated food or beverages. For many neurotoxicants (like industrial solvents), absorption of the substance through intact skin is a main route of exposure. Impermeable gloves, aprons and other appropriate equipment must therefore be provided to prevent skin absorption. This would be in addition to engineering controls or personal respiratory protection equipment. Considerable planning must be given to match personal protective equipment to the specific work being performed.
Administrative Controls
Administrative controls consist of managerial efforts to reduce workplace hazards through planning, training, employee rotation on job sites, changes in production processes, and product substitution (Urie 1992), as well as strict adherence to all existing regulations.
Workers’ Right-to-Know
While the employer bears the responsibility for providing a workplace or work experience that does not harm workers’ health, workers have the responsibility to follow workplace rules that are intended to protect them. Workers must be in a position to know what actions to take in protecting themselves. This means workers have the right to know about the neurotoxicity of substances with which they come into contact, and what protective measures they can take.
Worker Health Surveillance
Where conditions permit, workers should be regularly given medical examinations. A regular evaluation by occupational physicians or other medical specialists constitutes worker health surveillance. For workers known to be working with or around neurotoxicants, physicians should be knowledgeable of the effects of exposure. For example, low-level exposure to many organic solvents will produce symptoms of fatigue, sleep disorders, headaches and memory disturbances. For heavy doses of lead, wrist drop and peripheral nerve impairment would be signs of lead intoxication. Any signs and symptoms of neurotoxicant intoxication should result in reassignment of the worker to an area free of the neurotoxicant, and efforts to reduce workplace levels of the neurotoxicant.