Divine Aleru is an accomplished biochemist and researcher with a specialized background in environmental toxicology, focusing on the impacts of heavy metals on human health. With deep-rooted expertise in microbiome signatures analysis, Divine seamlessly blends rigorous scientific training with her passion for deciphering the intricate relationships between environmental exposures and the human microbiome. Her career is distinguished by a commitment to advancing integrative health interventions, leveraging cutting-edge microbiome research to illuminate how toxic metals shape biological systems. Driven by curiosity and innovation, Divine is dedicated to translating complex environmental findings into actionable insights that improve individual and public health outcomes. 
Divine Aleru is an accomplished biochemist and researcher with a specialized background in environmental toxicology, focusing on the impacts of heavy metals on human health. With deep-rooted expertise in microbiome signatures analysis, Divine seamlessly blends rigorous scientific training with her passion for deciphering the intricate relationships between environmental exposures and the human microbiome. Her career is distinguished by a commitment to advancing integrative health interventions, leveraging cutting-edge microbiome research to illuminate how toxic metals shape biological systems. Driven by curiosity and innovation, Divine is dedicated to translating complex environmental findings into actionable insights that improve individual and public health outcomes. What was issued?
Regulators and risk managers received an updated hexavalent chromium inhalation cancer risk assessment from an epidemiologic cohort in Painesville, Ohio. The study expanded follow-up to 2011, added short-tenure workers, rebuilt exposure histories, and modeled lung cancer against cumulative airborne Cr(VI). The authors reported a significant lung cancer excess (SMR 186) and derived unit risks from Cox models after controlling for smoking and age at hire. The preferred linear model produced an occupational unit risk of 0.00166 per μg/m³ and an environmental unit risk of 0.00832 per μg/m³, both lower than earlier estimates for the same cohort. The paper linked these results to current benchmarks such as OSHA’s 5 μg/m³ PEL and NIOSH’s 0.2 μg/m³ REL to support policy decisions and program audits.
Who is affected?
Chrome plating, pigment, welding, refractory, and chromate production employers face direct exposure control duties. Food manufacturers, millers, spice processors, beverage plants, and distributors near industrial corridors face siting and ambient air concerns when they run ovens, roasters, or dryers that draw outdoor air. Workplace hygienists, public health officers, and certification bodies that audit air handling or environmental monitoring in facilities near sources need these risk factors to set plans that protect workers and neighbors. Communities downwind of legacy sites and small foundries also face incremental risk and need clear guidance that aligns with food safety plans and hazard analyses.
Most important findings
The analysis linked lung cancer to cumulative Cr(VI) exposure and found a linear exposure–response in the range covered by the cohort. The team controlled for smoking and age at hire and still measured strong exposure effects. The occupational unit risk reached 0.00166 per μg/m³; the environmental unit risk reached 0.00832 per μg/m³. The study did not find clear effects from exposure duration independent of dose, and it identified little evidence for nonlinearity in the modeled range. Trend tests showed no increase at the very lowest cumulative exposures but showed increasing risk at and above roughly 1.1–1.4 mg·m⁻³·years, with stronger signals as exposure bands rose. These results update earlier modeling that informed OSHA’s rulemaking and state ambient programs; they also ground practical comparisons to today’s ambient Cr(VI) levels, which many networks report below 0.1 ng/m³. The paper translated unit risks into simple program checks: continuous 45-year exposure at the PEL (5 μg/m³) would imply an excess cancer risk on the order of 8 per 1,000, while the REL (0.2 μg/m³) would imply about 3 per 10,000, which meets many occupational risk targets.
Key implications
Food businesses that operate near chromate sources need tighter air intake controls, better filtration on makeup air, and procurement checks for contractors who sandblast, weld, or chrome-plate parts on or near a site. Employers should verify Cr(VI) task inventories, measure personal and area exposures against the PEL and REL, and include cumulative-dose thinking in work-rotation and ventilation plans. Certification programs that audit HACCP or HARPC can reference this dose–response to justify stronger siting and intake air prerequisites, especially for spice, tea, and nut lines that trap fine particles. Local health teams can set action triggers that pair ambient checks with unit-risk math to guide public messaging and relocation of vulnerable intakes. Regulators can align enforcement with the unit-risk values, require exposure reconstruction during incident reviews, and request smoking data in worker cohorts to avoid bias during causal reviews.
Citation
Proctor, D. M., Suh, M., Mittal, L., Hirsch, S., Salgado, R. V., Bartlett, C., Landingham, C. V., Rohr, A., & Crump, K. (2015). Inhalation cancer risk assessment of hexavalent chromium based on updated mortality for Painesville chromate production workers. Journal of Exposure Science & Environmental Epidemiology, 26(2), 224. https://doi.org/10.1038/jes.2015.77
