Evaluation of an Occupational Safety and Health Training for Cannabis Cultivation Workers.

OBJECTIVES: As the commercial cannabis industry grows, there is an increased need to characterize potentially hazardous workplace exposures and provide training to workers to mitigate these exposures with the goal of reducing accidents and injuries from cannabis cultivation, processing, and manufacturing. Public health and safety stakeholders in Colorado developed a worker-focused training designed to improve hazard awareness, recognition, and controls related to commercial cannabis cultivation. This paper describes the evaluation of this training. METHODS: The training was a full day, in-person educational experience directed to workers in the cannabis cultivation industry. Training topics included an overview of occupational safety and health hazards, chemical exposures, slip, trips, and falls, repetitive motion, the application of the hierarchy of control including lockout/tagout, machine guarding, personal protective equipment, among others. Evaluation surveys assessed attendee demographics, perceived job hazards, confidence to change workplace practices, knowledge, training relevancy and quality, intent to change behavior, as well as barriers and resources. RESULTS: A total of 208 people attended the safety trainings. One hundred and thirty-four participants (64%) completed the pre-training survey and 107 (51%) completed the post-training survey. Respondents provided high ratings for the quality and relevance of the training, with 91.3% of respondents rating the training very good or excellent. Before the training, the attendees listed their most concerning safety and health issues as exposure to pesticides and other chemicals (65.7%), absorbing chemicals through the skin (56.7%), slips, trips, and falls (52.2%), and respiratory hazards (50.7%). After the training, they reported the most concerning hazards to be slips, trips, and fall hazards (65.4%), ergonomic problems (64.5%), and respiratory issues (61.7%). There was a statistically non-significant increase in knowledge scores from 67.1% correct to 76.0% correct. Finally, 88.5% of respondents felt extremely or very confident that they could change their own health and safety practices at work. CONCLUSIONS: The training successfully reached cannabis employees in cultivation, compliance, and management. Survey respondents felt that the training was of high quality and addressed gaps in their knowledge related to safety and health hazards in the cannabis industry. The workplace safety and health concerns shifted from pre- to post-training. There was a statistically non-significant increase in knowledge. Additional follow-up of training attendees would be beneficial to measure sustained impact of training.

Potential exposures associated with indoor marijuana growing operations.

We entered a total of 30 indoor marijuana grow operations (IMGO) with law enforcement investigators in order to determine potential exposures to first responders. Samples for airborne fungal spores, volatile organic compounds, carbon dioxide, carbon monoxide, and delta-9-tetrahydrocannabinol (THC) were obtained as well as the identification of chemicals utilized in the IMGO. The chemicals utilized within the IMGOs were primarily pesticides and fertilizers with none showing high toxicity. Although several of the IMGOs had CO2 enrichment processes involving combustion, CO levels were not elevated. THC levels were identified on surfaces within the IMGOs and on the hands of the investigators. Surface levels ranged from <0.1 µg /100 cm(2) to 2000 µg /100 cm(2) with a geometric mean of 0.37 µg /100 cm(2). THC levels on the hands of officers ranged from <0.10 µg /wipe to 2900 µg /wipe with a geometric mean of 15 µg /wipe. These levels were not considered to be elevated to the point of causing a toxic exposure to responders. A total of 407 fungal spore samples were taken using both slit impactor plates and 400-hole impactors. Both methods identified elevated fungal spore levels, especially during the removal of plants from some of the IMGOs. After plant removal, spore counts increased to levels above 50,000 spores/m(3) with one sample over 500,000 spores/m(3). In addition, we found that there was a shift in species between indoor and outdoor samples with Cladosporium sp. the predominant outdoor species and Penicillium sp. the predominant indoor species. We concluded that the potential increase in fungal spore concentrations associated with the investigation and especially removal of the marijuana plants could potentially expose responders to levels of exposure consistent with those associated with mold remediation processes and that respiratory protection is advisable.

Decontamination of clothing and building materials associated with the clandestine production of methamphetamine.

This study was designed to determine how easily methamphetamine can be removed from clothing and building materials, utilizing different cleaning materials and methods. The study also addressed the penetration of methamphetamine into drywall and the ability of paints to encapsulate the methamphetamine on drywall. Clothing and building materials were contaminated in a stainless steel chamber by aerosolizing methamphetamine in a beaker heater. The amount of methamphetamine surface contamination was determined by sampling a grid pattern on the material prior to attempting to clean the materials. After cleaning, the materials were again sampled, and the degree of decontamination noted. We found that household clothing and response gear worn by first responders was easily decontaminated using a household detergent in a household washing machine. A single wash removed over 95% of the methamphetamine from these materials. The study also indicated that methamphetamine-contaminated, smooth non-porous surfaces can be easily cleaned to below detectable levels using only mild cleaners. More porous surfaces such as plywood and drywall were unlikely to be decontaminated to below regulatory levels even with three washes using a mild cleaner. This may be due to methamphetamine penetration into the paint on these surfaces. Evaluation of methamphetamine contamination on drywall indicated that approximately 40% of the methamphetamine was removed using a wipe, while another 60% remained in the paint layer. Stronger cleaners such as those with active ingredients including sodium hypochlorite or quaternary ammonia and commercial decontamination agents were more effective than mild detergent-based cleaners and may reduce methamphetamine contamination to below regulatory levels. Results from the encapsulation studies indicate that sprayed on oil-based paint will encapsulate methamphetamine on drywall and plywood surfaces up to 4.5 months, while latex paints were less effective.

Variability and specificity associated with environmental methamphetamine sampling and analysis.

This study was designed to explore the efficacy of the use of wipe sampling to determine methamphetamine contamination associated with the clandestine manufacture of methamphetamine. Three laboratories were utilized to analyze wipe samples to investigate variability in reported methamphetamine concentration among samples spiked with known amounts of methamphetamine. Different sampling media, surfaces, and solvents were also utilized to determine potential differences in measured methamphetamine concentration due to different wipes, wipe solvents, and wipe contaminants. This study examined rate of false positive detection among blank samples and whether interference with common household substances would create a false positive detection of methamphetamine. Variability between the three labs-using liquid chromatography with mass spectrometry or gas chromatography with mass spectrometry for detection of a known concentration of methamphetamine-resulted in percent differences of 3-30%. Results from wipe sample analysis for methamphetamine, using methanol or isopropanol, showed no significant difference in methamphetamine contamination recovery. Dust and paint contamination on methamphetamine wipe samples with known methamphetamine spike amounts did not affect methamphetamine wipe sample recovery. This study confirmed that either methanol or isopropanol is an appropriate solvent for use in methamphetamine wipe sampling. Dust and paint contamination on wipe samples will not interfere with the wipe sample analysis for methamphetamine. False positive detection for methamphetamine was not observed in any of the blank wipe samples submitted for the study. Finally, this study determined that methamphetamine will not be detected in structures that are truly methamphetamine free at current laboratory limits of quantification.

Risk of chronic beryllium disease by HLA-DPB1 E69 genotype and beryllium exposure in nuclear workers.

RATIONALE: Beryllium sensitization (BeS) and chronic beryllium disease (CBD) are determined by at least one genetic factor, a glutamic acid at position 69 (E69) of the HLA-DPB1 gene, and by exposure to beryllium. The relationship between exposure and the E69 genotype has not been well characterized. OBJECTIVES: The study goal was to define the relationship between beryllium exposure and E69 for CBD and BeS. METHODS: Workers (n = 386) from a U.S. nuclear weapons facility were enrolled into a case-control study (70 BeS, 61 CBD, and 255 control subjects). HLA-DPB1 genotypes were determined by sequence-specific primer-polymerase chain reaction. Beryllium exposures were reconstructed on the basis of worker interviews and historical exposure measurements. MEASUREMENTS AND MAIN RESULTS: Any E69 carriage increased odds for CBD (odds ratio [OR], 7.61; 95% confidence interval [CI], 3.66-15.84) and each unit increase in lifetime weighted average exposure increased the odds for CBD (OR, 2.27; 95% CI, 1.26-4.09). Compared with E69-negative genotypes, a single E69-positive *02 allele increased the odds for BeS (OR, 12.01; 95% CI, 4.28-33.71) and CBD (OR, 3.46; 95% CI, 1.42-8.43). A single non-*02 E69 allele further increased the odds for BeS (OR, 29.54; 95% CI, 10.33-84.53) and CBD (OR, 11.97; 95% CI, 5.12-28.00) and two E69 allele copies conferred the highest odds for BeS (OR, 55.68; 95% CI, 14.80-209.40) and CBD (OR, 22.54; 95% CI, 7.00-72.62). CONCLUSIONS: E69 and beryllium exposure both contribute to the odds of CBD. The increased odds for CBD and BeS due to E69 appear to be differentially distributed by genotype, with non-*02 E69 carriers and E69 homozygotes at higher odds than those with *02 genotypes.