Step 4 involves the study of exposure pathways. Steps 5 and 6 use
epidemiological and toxicological information on dose-incidence and
dose-response relationships between environmental parameters and
specific health effects. Step 7 can be used to evaluate the significance
and acceptability of adverse health effects, and Step 8 focuses
on mitigation measures. Finally, Step 9 involves appropriate
decision making. This generic EHIA methodology has been modified
to allow its use for chemical manufacturing facilities (World
Health Organization, 1987).