I need articles and experimental design for the effect of Environmental exposure to certain chemicals/toxins/genes on susceptibility and protection of Opioid and substance abusers to death.
Definitely yes. Several genes (together with environmental factors) play a role in the susceptibility to substance abuse. For example: genes like OPRM1 and DRD2 play a major role toward the "reward" domain of substance abuse. Genes like NPY and COMT play a role toward the "resilience" domain of addiction. Check these studies:
1. Article Genes and Addictions
2. Article Genetic and Environmental Influences on Substance Initiation...