Research and Faculty

Pilot Project Research Training (PPRT) Program

The goal of the PPRT program is to strengthen the occupational health and safety research capacity of the United States by increasing the number and quality of scientists who pursue research careers in OH&S disciplines. The PPRT program provides short-term seed funds to support innovative pilot research projects.

The 2022-2023 request for proposal deadline for applications was Thursday May 5th, 2022 5:00pm EDT



The Current 2022-2023 cycle is over, but we will be announcing a new deadline soon for the 2023-2024 cycle!

Between now and May 2023 Adam Finkel, PPRT Director is happy to answer any questions:


Our Faculty

COHSE is fortunate to have many faculty members with strong research records that cover a broad spectrum of occupational health and safety (OH&S) issues.


Our faculty have strong research programs with many recent publications.

Recent Publications

September 2022
Health Effects of Pesticide Exposure in Latin American and the Caribbean Populations: A Scoping Review
Alexis J Handal

Environ Health Perspect. 2022 Sep;130(9):96002. doi: 10.1289/EHP9934. Epub 2022 Sep 29.


BACKGROUND: Multiple epidemiological studies have shown that exposure to pesticides is associated with adverse health outcomes. However, the literature on pesticide-related health effects in the Latin American and the Caribbean (LAC) region, an area of intensive agricultural and residential pesticide use, is sparse. We conducted a scoping review to describe the current state of research on the health effects of pesticide exposure in LAC populations with the goal of identifying knowledge gaps and research capacity building needs.

METHODS: We searched PubMed and SciELO for epidemiological studies on pesticide exposure and human health in LAC populations published between January 2007 and December 2021. We identified 233 publications from 16 countries that met our inclusion criteria and grouped them by health outcome (genotoxicity, neurobehavioral outcomes, placental outcomes and teratogenicity, cancer, thyroid function, reproductive outcomes, birth outcomes and child growth, and others).

RESULTS: Most published studies were conducted in Brazil (37%, n=88) and Mexico (20%, n=46), were cross-sectional in design (72%, n=167), and focused on farmworkers (45%, n=105) or children (21%, n=48). The most frequently studied health effects included genotoxicity (24%, n=62) and neurobehavioral outcomes (21%, n=54), and organophosphate (OP) pesticides were the most frequently examined (26%, n=81). Forty-seven percent (n=112) of the studies relied only on indirect pesticide exposure assessment methods. Exposure to OP pesticides, carbamates, or to multiple pesticide classes was consistently associated with markers of genotoxicity and adverse neurobehavioral outcomes, particularly among children and farmworkers.

DISCUSSION: Our scoping review provides some evidence that exposure to pesticides may adversely impact the health of LAC populations, but methodological limitations and inconsistencies undermine the strength of the conclusions. It is critical to increase capacity building, integrate research initiatives, and conduct more rigorous epidemiological studies in the region to address these limitations, better inform public health surveillance systems, and maximize the impact of research on public policies.

PMID:36173136 | DOI:10.1289/EHP9934

September 2022
Level of Concern, Spending, and External Support Related to COVID-19: A Comparison between Working and Non-Working Older Adults
Aurora B Le

Int J Environ Res Public Health. 2022 Sep 9;19(18):11375. doi: 10.3390/ijerph191811375.


This study compared levels of concern, spending, and use of external support by working status among older adults in the U.S. during the COVID-19 pandemic. It assessed whether work influences these variables related to wellness. Data from 2489 older adults from the 2020 U.S. Health and Retirement Study were analyzed using multiple linear and logistic regression. Older adults who worked had lower concerns about the pandemic (β = -0.28, p = 0.048), were less likely to increase their spending (OR = 0.74, p = 0.041), and were less likely to use external support (OR = 0.50, p < 0.001). Use of external support increased with age (OR = 1.04, p < 0.001) and increased spending (OR = 1.32, p = 0.019). Married older adults were less likely to increase spending (OR = 0.75, p = 0.007) and had lower concerns toward COVID-19 (β = -0.28, p = 0.011). Higher levels of concern were reported among women (β = 0.31, p = 0.005) and participants who had friends or family members diagnosed with COVID-19 (β = 0.51, p < 0.001). Women were more likely to use support (OR = 1.80, p < 0.001). Work appears to bolster older adult wellness outcomes.

PMID:36141641 | DOI:10.3390/ijerph191811375

September 2022
Associations of urinary phthalate metabolites and inflammatory biomarkers among pregnant women in Puerto Rico
John D Meeker

Sci Total Environ. 2022 Sep 13;854:158773. doi: 10.1016/j.scitotenv.2022.158773. Online ahead of print.


Phthalates are ubiquitous environmental exposures that may be implicated in inflammatory processes, as demonstrated by previous in vivo and in vitro studies. Few human studies have substantiated these observations. This study sought to examine whether maternal phthalate exposures impact inflammatory processes, as measured by circulating inflammatory biomarkers, in the PROTECT cohort in northern Puerto Rico. Inflammatory biomarkers included matrix metalloproteinases 1, 2, and 9 (MMPs), C-reactive protein (CRP), vascular cell adhesion molecule-1 (VCAM), and intercellular cell adhesion molecule-1 (ICAM). Biomarkers were measured in maternal serum samples collected during pregnancy. 19 phthalate metabolites were assessed in urinary samples collected at three study visits across pregnancy. Phthalates with <50 % of measurements above the limit of detection were excluded from analysis. We utilized linear mixed effect models to estimate associations between interquartile range increases in phthalate metabolite concentrations and percent changes in inflammatory biomarkers. Our results revealed significant associations between mono-n-butyl phthalate (MBP) and higher MMP1 by 7.86 % (95 % CI: 0.49, 15.76) and between mono oxononyl phthalate (MONP) and higher MMP2 by 8.30 % (95 % CI: 2.22, 14.75). We observed negative or null associations between phthalate metabolites and MMP2, MMP9, ICAM, VCAM, and CRP. Many results were significantly modified by fetal sex, particularly those between di-2-ethylhexyl phthalate (DEHP) metabolites and MMP1 (p-interaction: MEHHP = 0.01, MEOHP = 0.04, MECPP = 0.01) and MMP2 (p-interaction: MEHHP = 0.03, MEOHP = 0.01, MECPP = 0.01), for which associations were positive among only women carrying female fetuses. MMPs have been previously associated with preeclampsia and hypertensive pregnancy disorders as mediators of artery remodeling. Hence, our findings suggest a potential role for phthalates in mediating the maternal inflammatory response, as well as significant sexual dimorphism in these relationships, which has implications for several adverse pregnancy outcomes.

PMID:36113809 | DOI:10.1016/j.scitotenv.2022.158773

September 2022
Users Maintain Task Accuracy and Gait Characteristics During Missed Exoskeleton Actuations Through Adaptations In Joint Kinematics
Leia Stirling

Annu Int Conf IEEE Eng Med Biol Soc. 2022 Jul;2022:1809-1813. doi: 10.1109/EMBC48229.2022.9871773.


In operational settings, lower-limb active exoskeletons may experience errors, where an actuation that should be present is missed. These missed actuations may impact users’ trust in the system and the adapted human-exoskeleton coordination strategies. In this study, we introduced pseudorandom catch trials, in which an assistive exoskeleton torque was not applied, to understand the immediate responses to missed actuations and how users’ internal models to an exoskeleton adapt upon repeated exposure to missed actuations. Participants (N = 15) were instructed to complete a stepping task while wearing a bilateral powered ankle exoskeleton. Human-exoskeleton coordination and trust were inferred from task performance (step accuracy), step characteristics (step length and width), and joint kinematics at selected peak locations of the lower limb. Step characteristics and task accuracy were not impacted by the loss of exoskeleton torque as hip flexion was modulated to support completing the stepping task during catch trials, which supports an impacted human-exoskeleton coordination. Reductions in ankle plantarflexion during catch trials suggest user adaptation to the exoskeleton. Trust was not impacted by catch trials, as there were no significant differences in task performance or gait characteristics between earlier and later strides. Understanding the interactions between human-exoskeleton coordination, task accuracy, and step characteristics will support development of exoskeleton controllers for non-ideal operational settings.

PMID:36086362 | DOI:10.1109/EMBC48229.2022.9871773

September 2022
Exposure to melamine and its derivatives and aromatic amines among pregnant women in the United States: The ECHO Program
John D Meeker

Chemosphere. 2022 Nov;307(Pt 2):135599. doi: 10.1016/j.chemosphere.2022.135599. Epub 2022 Aug 30.


BACKGROUND: Melamine, melamine derivatives, and aromatic amines are nitrogen-containing compounds with known toxicity and widespread commercial uses. Nevertheless, biomonitoring of these chemicals is lacking, particularly during pregnancy, a period of increased susceptibility to adverse health effects.

OBJECTIVES: We aimed to measure melamine, melamine derivatives, and aromatic amine exposure in pregnant women across the United States (U.S.) and evaluate associations with participant and urine sample collection characteristics.

METHODS: We measured 43 analytes, representing 45 chemicals (i.e., melamine, three melamine derivatives, and 41 aromatic amines), in urine from pregnant women in nine diverse ECHO cohorts during 2008-2020 (N = 171). To assess relations with participant and urine sample collection characteristics, we used generalized estimating equations to estimate prevalence ratios (PRs) for analytes dichotomized at the detection limit, % differences (%Δ) for continuous analytes, and 95% confidence intervals. Multivariable models included age, race/ethnicity, marital status, urinary cotinine, and year of sample collection.

RESULTS: Twelve chemicals were detected in >60% of samples, with near ubiquitous detection of cyanuric acid, melamine, aniline, 4,4′-methylenedianiline, and a composite of o-toluidine and m-toluidine (99-100%). In multivariable adjusted models, most chemicals were associated with higher exposures among Hispanic and non-Hispanic Black participants. For example, concentrations of 3,4-dichloroaniline were higher among Hispanic (%Δ: +149, 95% CI: +17, +431) and non-Hispanic Black (%Δ: +136, 95% CI: +35, +311) women compared with non-Hispanic White women. We observed similar results for ammelide, o-/m-toluidine, 4,4′-methylenedianiline, and 4-chloroaniline. Most chemicals were positively associated with urinary cotinine, with strongest associations observed for o-/m-toluidine (%Δ: +23; 95% CI: +16, +31) and 3,4-dichloroaniline (%Δ: +25; 95% CI: +17, +33). Some chemicals exhibited annual trends (e.g., %Δ in melamine per year: -11; 95% CI: -19, -1) or time of day, seasonal, and geographic variability.

DISCUSSION: Exposure to melamine, cyanuric acid, and some aromatic amines was ubiquitous in this first investigation of these analytes in pregnant women. Future research should expand biomonitoring, identify sources of exposure disparities by race/ethnicity, and evaluate potential adverse health effects.

PMID:36055588 | DOI:10.1016/j.chemosphere.2022.135599

September 2022
Evaluating Occupational Noise Exposure as a Contributor to Injury Risk among Miners
Richard L Neitzel

Ann Work Expo Health. 2022 Sep 2:wxac059. doi: 10.1093/annweh/wxac059. Online ahead of print.


OBJECTIVES: This study: (i) assessed the relationship between noise exposure and injury risk, comprehensively adjusting for individual factors, psychosocial stressors, and organizational influences; (ii) determined the relative importance of noise on injuries; (iii) estimated the lowest observed adverse effect level (LOAEL) of noise on injury risk to determine the threshold of noise considered hazardous to injuries; and (iv) quantified the fraction of injuries that could be attributed to hazardous noise exposure.

METHODS: In this cross-sectional study at 10 US surface mine sites, traditional mixed effects, Poisson regression, and boosted regression tree (BRT) models were run on the number of reported work-related injuries in the last year. The LOAEL of noise on injuries was identified by estimating the percent increase in work-related injuries at different thresholds of noise exposure using a counterfactual estimator through the BRT model. A population attributable fraction (PAF) was quantified with this counterfactual estimator to predict reductions in injuries at the LOAEL.

RESULTS: Among 18 predictors of work-related injuries, mine site, perceived job safety, age, and sleepiness were the most important predictors. Occupational noise exposure was the seventh most important predictor. The LOAEL of noise for work-related injuries was a full-shift exposure of 88 dBA. Exposure ≥88 dBA was attributed to 20.3% (95% CI: 11.2%, 29.3%) of reported work-related injuries in the last year among the participants.

CONCLUSIONS: This study further supports hypotheses of a dose-response relationship between occupational noise exposure and work-related injuries, and suggests that exposures ≥88 dBA may increase injury risk in mining.

PMID:36053031 | DOI:10.1093/annweh/wxac059

September 2022
Challenges in Quantifying Heel-Lift During Spacesuit Gait
Leia Stirling

Aerosp Med Hum Perform. 2022 Aug 1;93(8):643-648. doi: 10.3357/AMHP.5961.2022.


INTRODUCTION: Heel-lift is a subjectively reported fit issue in planetary spacesuit boot prototypes that has not yet been quantified. Inertial measurement units (IMUs) could quantify heel-lift but are susceptible to integration drift. This work evaluates the use of IMUs and drift-correction algorithms, such as zero-velocity (ZVUs) and zero-position updates (ZPUs), to quantify heel-lift during spacesuited gait.METHODS: Data was originally collected by Fineman et al. in 2018 to assess lower body relative coordination in the spacesuit. IMUs were mounted on the spacesuit lower legs (SLLs) and spacesuit operator’s shank as three operators walked on a level walkway in three spacesuit padding conditions. Discrete wavelet transforms were used to identify foot-flat phase and heel-off for each step. Differences in heel-off timepoints were calculated in each step as a potential indicator of heel-lift, with spacesuit-delayed heel-off suggesting heel-lift. Average drift rates were estimated prior to and after applying ZVUs and ZPUs.RESULTS: Heel-off timepoint differences showed instances of spacesuit-delayed heel-off and instances of operator-delayed heel-off. Drift rates after applying ZVUs and ZPUs suggested an upper time bound of 0.03 s past heel-off to measure heel-lift magnitude with an accuracy of 1 cm.DISCUSSION: Results suggest that IMUs may not be appropriate for quantifying the presence and magnitude of heel lift. Operator-delayed heel-off suggests that the SLL may be expanding prior to heel-off, creating a false vertical acceleration signal interpreted by this study to be spacesuit heel-off. Quantifying heel-off will therefore require improvements in IMU mounting to mitigate the effects of SLL, or alternative sensor technologies.Boppana A, Priddy ST, Stirling L, Anderson AP. Challenges in quantifying heel-lift during spacesuit gait. Aerosp Med Hum Perform. 2022; 93(8):643-648.

PMID:36050859 | DOI:10.3357/AMHP.5961.2022

August 2022
Trimester-specific phthalate exposures in pregnancy are associated with circulating metabolites in children
John D Meeker

PLoS One. 2022 Aug 30;17(8):e0272794. doi: 10.1371/journal.pone.0272794. eCollection 2022.


BACKGROUND: Prenatal phthalates exposures have been related to adiposity in peripuberty in a sex-specific fashion. Untargeted metabolomics analysis to assess circulating metabolites offers the potential to characterize biochemical pathways by which early life exposures influence the development of cardiometabolic risk during childhood and adolescence, prior to becoming evident in clinical markers.

METHODS: Among mother-child dyads from the Early Life Exposure in Mexico to ENvironmental Toxicants (ELEMENT) birth cohort, we measured 9 phthalate metabolites and bisphenol A in maternal spot urine samples obtained during each trimester of pregnancy, corrected for urinary specific gravity and natural log-transformed. In 110 boys and 124 girls aged 8-14 years, we used a mass-spectrometry based untargeted metabolomics platform to measure fasting serum metabolites, yielding 572 annotated metabolites. We estimated the associations between trimester-specific urinary toxicants and each serum metabolite, among all children or stratified by sex and adjusting for child age, BMI z-score, and pubertal onset. We accounted for multiple comparisons using a 10% false discovery rate (q<0.1).

RESULTS: Associations between exposures and metabolites were observed among all children and in sex-stratified analyses (q<0.1). First trimester MEP, MiBP, and MCPP were associated with decreased 2-deoxy-D-glucose among all children. Among girls, third trimester concentrations of MECPP, MEHHP, MEHP, and MCPP were associated with 15, 13, 1, and 10 metabolites, respectively, including decreased choline and increased acylcarnitines and saturated FAs (FA). Among boys, third trimester MIBP was positively associated with 9 features including long chain saturated FAs, and second trimester MBzP was inversely associated with thyroxine.

CONCLUSIONS: Metabolomics biomarkers may reflect sex- and exposure timing-specific responses to prenatal phthalate exposures manifesting in childhood that may not be detected using standard clinical markers of cardiometabolic risk.

PMID:36040907 | PMC:PMC9426875 | DOI:10.1371/journal.pone.0272794

August 2022
Maternal blood metal concentrations are associated with C-reactive protein and cell adhesion molecules among pregnant women in Puerto Rico
John D Meeker

Environ Epidemiol. 2022 Jul 5;6(4):e214. doi: 10.1097/EE9.0000000000000214. eCollection 2022 Aug.


Studies have revealed a link between aberrant levels of maternal C-reactive protein (CRP) and cell adhesion molecules (CAMs) with adverse birth outcomes. Some epidemiologic studies have indicated that long-term metal exposures can modulate the levels of CRP and CAMs, but the associations between prenatal metal exposures and the levels of CRP and CAMs have yet to be studied more extensively. In this study, we assessed associations between maternal blood metal levels and CRP/CAMs among 617 pregnant women in the Puerto Rico PROTECT birth cohort.

METHODS: Blood samples were collected from participants at 16-20 (visit 1) and 24-28 (visit 3) weeks gestation. We measured concentrations of 11 metals using inductively coupled plasma mass spectrometry (ICP-MS). From the blood samples, CRP and CAMs intercellular adhesion molecule (ICAM) and vascular cell adhesion molecule (VCAM) were also quantified using a customized Luminex assay. Linear-mixed effects models (LMEs) were used to regress CRP and CAMs on metals and included random intercepts for study participants to account for correlated repeated outcome measures. Fetal sex and visit effects were estimated using interaction terms between metal exposure variables and fetal sex, as well as visit indicators, respectively.

RESULTS: We observed significant positive associations between nickel and CRP (Δ: 7.04, 95% CI = 0.75, 13.73) and between lead and VCAM (Δ: 4.57, 95% CI = 1.36, 7.89). The positive associations were mainly driven by mothers carrying male fetuses. We also observed various visit-specific associations. The significant associations between metals and CRP were predominantly driven by visit 3; however, the significant associations between metals and VCAM were mainly driven by visit 1.

CONCLUSION: Certain maternal blood metal levels were significantly associated with CRP and CAMs and most of these associations were differentially driven by fetal sex, as well as by timing in pregnancy. Future studies should further explore metal-CRP/CAMs associations for a better understanding of the underlying mechanism of metal-induced adverse birth outcomes.

PMID:35975168 | PMC:PMC9374188 | DOI:10.1097/EE9.0000000000000214

August 2022
Service Workers’ Experience and Perceptions of Workplace Protective Measures During the Onset of COVID-19
Marie-Anne S Rosemberg

Workplace Health Saf. 2022 Aug 8:21650799221101001. doi: 10.1177/21650799221101001. Online ahead of print.


OBJECTIVES: The Coronavirus-2019 (COVID-19) pandemic presents a unique burden specifically for workers in service industries. However, limited research on service worker’s experience during the onset of COVID-19 exists. We aimed to describe the experiences and concerns of service industry workers during the pandemic’s onset.

METHODS: This is a mixed-method study. Participants were recruited through social media and completed either a survey or a phone interview during May and June 2020. The survey and transcribed interview data were analyzed using the SPSS software and content analysis, respectively.

RESULTS: Twenty-seven individuals completed audio-recorded phone interviews and 28 completed the survey. Participants were mostly women between 19 and 65 years old. Participants worked in food retail (n = 23), restaurant (n = 25), and hospitality (n = 7) industries. There was discordance in perceived threat level of COVID-19. Most participants reported that their workplace complied with their state’s mandates for protection measures, while others reported lacking basic supplies such as soap, hand sanitizer, and masks. Job insecurity, change of job tasks, and work hours were the most common ways that COVID-19 affected the workers. Worker’s assertiveness to self-protect while at work was influenced by their perceived severity of the pandemic.

CONCLUSION/APPLICATION TO PRACTICE: This study highlights the vulnerability of service workers relating to job security and job tasks during the pandemic. Organizational processes are needed to promote safe work environments and facilitate access to resources for these workers. In addition, occupational health practitioners need to be aware of and address the emerging health risks and worker needs.

PMID:35942581 | DOI:10.1177/21650799221101001

worker safety
worker safety
worker safety


Keeping e-waste workers healthy and safe

In an interview with Rick Nietzel, we learn about the rewarding experiences of students working with electronic waste abroad in Thailand, with photos and videos illustrating the type of work being done with this project.


Death of a Flip Phone

In an informational video describing the dangerous metals and plastic compounds contained in old phones, we learn about the ways electronic waste negatively affects the environment when it is not properly managed.