This review evaluates the sources of lead exposure worldwide. Studies from searches relating to sources of lead exposure in various countries within different regional zones were reviewed. Results indicated that in Nigeria, exposure sources include electronic waste, paint and batteries. In Mexico exposure sources include glazed ceramics, lead contaminated utensils and lead contaminated water, for India lead sources include cosmetics and traditional medicines. Sources of lead exposure in China include e-waste, traditional medicines and industrial emissions. In France, exposure sources included lead paint from older homes, imported ceramics and cosmetics and industrial emissions. Australia’s exposure sources include paint, dust, imported toys and traditional medicines. Finally, in the United States exposure sources included paint, the industrial legacy of lead exposure and batteries. In high-income countries (HICs) the legacy of lead exposure keeps populations continuously exposed. In lower- and middle-income countries (LMICs), in addition to the legacy of lead exposure, lack of regulations or the inability to enforce regulations keeps populations exposed. In all, evidence suggests that lead exposure remains an issue of public health significance in both HIC and LMIC.

Lead exposure and a marker of oxidative stress (gamma-glutamyl transferase—GGT), and their effects on life course variables (age, country of birth, education levels, gender, ethnicity, income, and occupation) were explored in this cross-sectional study of United States (U.S.) adults’ ≥ 20 years of age via the National Health and Nutrition Examination Survey (NHANES) 2007–2010 datasets. Country of birth, education levels, gender, ethnicity, income, and occupation showed significant differences depending on the degree of lead exposure, with higher levels of exposure resulting in worse outcomes. Age and GGT were significantly associated with lead exposure. More must be done to mitigate sources of lead exposure, to prevent it from altering the life course of at-risk populations.

This study characterizes potential soil lead (Pb) exposure risk at the household scale in Greensboro, North Carolina, using an innovative combination of field sampling, statistical analysis, and machine-learning techniques. Soil samples were collected at the dripline, yard, and street side at 462 households (total sample size = 2310). Samples were analyzed for Pb and then combined with publicly available data on potential historic Pb sources, soil properties, and household and neighborhood demographic characteristics. This curated data set was then analyzed with statistical and machine-learning techniques to identify the drivers of potential soil Pb exposure risks and to build predictive models. Among all samples, 43% exceeded current guidelines for Pb in residential gardens. There were significant racial disparities in potential soil Pb exposure risk; soil Pb at the dripline increased by 19% for every 25% increase in the neighborhood population identifying as Black. A machine-learned Bayesian network model was able to classify residential parcels by risk of exceeding residential gardening standards with excellent reproducibility in cross validation. These findings underscore the need for targeted outreach programs to prevent Pb exposure in residential areas and demonstrate an approach for prioritizing outreach locations.

Cardiovascular-related clinical markers were evaluated in this cross-sectional study of United States adults (aged ≥ 20) exposed to lead via the National Health and Nutrition Examination Survey 2007–2008 and the 2009–2010 datasets. In four quartiles of exposure—0–2 μg/dL, 2–5 μg/dL, 5–10 μg/dL, and 10 μg/dL and over, clinical and anthropometric markers were evaluated—to examine how the markers manifested in the quartiles. Associations were determined via linear regression. Finally, clinical makers, and how they manifested between exposed and less-exposed occupations, were explored in addition to how duration of exposure altered these clinical markers. In regression analysis, Diastolic Blood Pressure (DBP) and high-density lipoprotein (HDL) cholesterol, were significantly associated with blood lead level (BLL). In the occupational analysis, Systolic Blood Pressure (SBP), DBP, C-reactive protein (CRP), triglycerides, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, showed differences between populations in the exposed and less-exposed occupations. Regarding Agriculture, Forestry & Fishing, the duration of exposure altered SBP, CRP, and LDL cholesterol. With mining, the duration of exposure altered SBP, DBP, triglycerides, and HDL cholesterol, whereas in construction, the duration in occupation altered SBP, triglycerides, and CRP. In conclusion, lead exposure has a profound effect on the cardiovascular system, with potentially adverse outcomes existing at all exposure levels.

This study explores the combined effect of lead (Pb) exposure and an index of chronic physiological stress on cardiovascular disease mortality using data from the National Health and Nutrition Examination Survey (NHANES) 1999–2008 linked to 1999–2014 National Death Index data. Chronic physiological stress was measured using the allostatic load (AL) index, which was formed by analyzing markers from the cardiovascular, inflammatory, and metabolic systems, with Pb levels, assessed using blood lead levels (BLL). The dataset was analyzed with statistical techniques to explore (a) the relationship between Pb exposure and AL, and (b) the combined role of Pb and AL on cardiovascular disease mortality. Results indicated that AL was more elevated in those with BLLs above the 50th percentile in the US population and that those with elevated AL were more likely to have high BLL. Finally, the interaction of AL and BLL significantly increased the likelihood of cardiovascular disease mortality. These findings highlight the need for considering the totality of exposures experienced by populations to build holistic programs to prevent Pb exposure and reduce stressors to promote optimal health outcomes and reduce cardiovascular mortality risk.

Chronic cadmium exposure and its effect on cardiovascular-related markers were explored in the cross-sectional study of U.S. adults using the National Health and Nutrition Examination Survey (NHANES) 2007–2010 data. Cardiovascular-related markers, such as LDL cholesterol mg/dL (LDL-C), non-HDL cholesterol mg/dL (non-HDL-C), triglycerides mg/dL (TG), c-reactive protein mg/dL (CRP), and gamma-glutamyl transferase U/L (GGT) were explored in relation to urine cadmium level µg/L (UCL). The variables and their relation to UCL µg/L were explored both as continuous and categorical variables using linear and logistic regression models and basic descriptive statistics. Geometric Mean values of the markers of interest were statistically significantly more elevated in middle-aged adults (45–65 years) as compared to younger adults (18–44 years). In linear regression analysis, CRP mg/dL, LDL-C mg/dL, non-HDL-C mg/dL, and GGT U/L levels were significantly associated with UCLs mg/dL after adjusting for confounding variables. In binary logistic regression models, young and middle-aged adults chronically exposed to cadmium were significantly more likely to have elevated CRP mg/dL levels. This study suggests that chronic exposure to cadmium alters cardiovascular-related markers in middle-aged adults more so than younger adults, which calls for early public health intervention to limit cadmium exposure in the U.S.