Outbreak of lead poisoning from a civilian indoor firing range in the UK.

INTRODUCTION: Lead exposure from discharged lead dust is a recognised risk at firing ranges. We report a lead poisoning outbreak among staff and their close contacts at a UK civilian indoor 24 m firing range. METHODS: A retrospective review was undertaken of data collected on all patients at risk of lead poisoning identified either by direct referral to the Clinical Toxicology clinicians at the West Midlands Poisons Unit, or via the Trace Elements Supra-Regional Assay Service Laboratory at Sandwell hospital. RESULTS: Eighty-seven patients were identified as having possible lead exposure, either at the firing range or via close contacts. Of these, 63 patients aged between 6 months and 78 years attended for blood lead concentration (BLC) testing. The highest BLC at presentation was 11.7 µmol/L (242 µg/dL). Only nine patients reported any symptoms at presentation. Fifteen patients received lead chelation therapy with oral dimercaptosuccinic acid (or succimer) 30 mg/kg/day or intravenous sodium calcium edetate (EDTA) 75 mg/kg/day, dependent on stock availability. DISCUSSION: This report highlights the need for vigilance of lead poisoning as an occupational hazard in the UK, including at recreational facilities such as indoor firing ranges. It emphasises the importance of regulation of lead exposure in the workplace, particularly given the vague symptoms of lead poisoning, and proposes re-appraisal of UK legislation. This report also highlights potential issues surrounding stock availability of rarely used antidotes for uncommon presentations in the event of an outbreak of poisoning.

The impact of childhood lead exposure on adult personality: Evidence from the United States, Europe, and a large-scale natural experiment.

Childhood lead exposure has devastating lifelong consequences, as even low-level exposure stunts intelligence and leads to delinquent behavior. However, these consequences may be more extensive than previously thought because childhood lead exposure may adversely affect normal-range personality traits. Personality influences nearly every aspect of human functioning, from well-being to career earnings to longevity, so effects of lead exposure on personality would have far-reaching societal consequences. In a preregistered investigation, we tested this hypothesis by linking historic atmospheric lead data from 269 US counties and 37 European nations to personality questionnaire data from over 1.5 million people who grew up in these areas. Adjusting for age and socioeconomic status, US adults who grew up in counties with higher atmospheric lead levels had less adaptive personality profiles: they were less agreeable and conscientious and, among younger participants, more neurotic. Next, we utilized a natural experiment, the removal of leaded gasoline because of the 1970 Clean Air Act, to test whether lead exposure caused these personality differences. Participants born after atmospheric lead levels began to decline in their county had more mature, psychologically healthy adult personalities (higher agreeableness and conscientiousness and lower neuroticism), but these findings were not discriminable from pure cohort effects. Finally, we replicated associations in Europeans. European participants who spent their childhood in areas with more atmospheric lead were less agreeable and more neurotic in adulthood. Our findings suggest that further reduction of lead exposure is a critical public health issue.

Clinical case analysis of 32 children aged 0-6 years with lead poisoning in Nanning, China.

Lead is one of the heavy metals that is toxic and widely distributed in the environment, and children are more sensitive to the toxic effects of lead because the blood-brain barrier and immune system are not yet well developed. The objective of the study was to investigate the clinical characteristics of lead poisoning in children aged 0∼6 years in a hospital in Guangxi, and to provide scientific basis for the prevention and treatment of lead poisoning. We collected and analyzed the clinical data of 32 children with lead poisoning admitted to a hospital in Guangxi from 2010 to 2018. The results showed that most of the 32 cases presented with hyperactivity, irritability, poor appetite, abdominal pain, diarrhea, or constipation. The hemoglobin (HGB), mean corpusular volume (MCV), mean corpuscular hemoglobin (MCH), and hematocrit (HCT) of the lead-poisoned children were all decreased to different degrees and were below normal acceptable levels. Urinary ß2-microglobulin was increased. Blood lead levels (BLL) decreased significantly after intravenous injection of the lead chelator, calcium disodium edetate (CaNa2-EDTA). In addition, HGB returned to normal levels, while MCV, MCH, and HCT increased but remained below normal levels. Urinary ß2-microglobulin was reduced to normal levels. Therefore, in this cohort of children, the high-risk factors for lead poisoning are mainly Chinese medicines, such as baby powder. In conclusion, lead poisoning caused neurological damage and behavioral changes in children and decreased erythrocyte parameters, leading to digestive symptoms and renal impairment, which can be attenuated by CaNa2-EDTA treatment.

Using exterior housing conditions to predict elevated pediatric blood lead levels.

Housing-based lead paint dust is the most common source of lead exposure for US-born children. Although year of housing construction is a critical indicator of the lead hazard to US children, not all housing of the same age poses the same risk to children. Additional information about housing condition is required to differentiate the housing-based lead risk at the parcel level. This study aimed to identify and assess a method for gathering and using observations of exterior housing conditions to identify active housing-based lead hazards at the parcel level. We used a dataset of pediatric blood lead observations (sample years 2000-2013, ages 6-72 months, n = 6,589) to assess associations between observations of exterior housing conditions and housing-based lead risk. We used graphical and Lasso regression methods to estimate the likelihood of an elevated blood lead observation (≥3.5 µg/dL). Our methods estimate a monotonic increase in the likelihood of an elevated blood lead observation as housing conditions deteriorate with the largest changes associated with homes in the greatest disrepair. Additionally we estimate that age of home construction works in consort with housing conditions to amplify risks among those houses built before 1952. Our analysis indicates that a survey of external housing conditions can be used in combination with age of housing in the identification process, at the parcel level, of homes that pose a housing-based lead hazard to children.

Using Artificial Intelligence to Identify Sources and Pathways of Lead Exposure in Children.

CONTEXT: Sources and pathways of lead exposure in young children have not been analyzed using new artificial intelligence methods. OBJECTIVE: To collect environmental, behavioral, and other data on sources and pathways in 17 rural homes to predict at-risk households and to compare urban and rural indicators of exposure. DESIGN: Cross-sectional pilot study. SETTING: Knox County, Illinois, which has a high rate of childhood lead poisoning. PARTICIPANTS: Rural families. METHODS: Neural network and K-means statistical analysis. MAIN OUTCOME MEASURE: Children's blood lead level. RESULTS: Lead paint on doors, lead dust, residential property assessed tax, and median interior paint lead level were the most important predictors of children's blood lead level. CONCLUSIONS: K-means analysis confirmed that settled house dust lead loadings, age of housing, concentration of lead in door paint, and geometric mean of interior lead paint samples were the most important predictors of lead in children's blood. However, assessed property tax also emerged as a new predictor. A sampling strategy that examines these variables can provide lead poisoning prevention professionals with an efficient and cost-effective means of identifying priority homes for lead remediation. The ability to preemptively target remediation efforts can help health, housing, and other agencies to remove lead hazards before children develop irreversible health effects and incur costs associated with lead in their blood.

Estimation of blood lead levels in the French population using two complementary approaches: Esteban (2014-2016) as part of the human biomonitoring program and the national surveillance system for childhood lead poisoning (2015-2018).

BACKGROUND: Used widely for centuries, lead is a common environmental pollutant. As a cumulative toxic, its presence in the body is always evidence of exposure, and health effects occur without threshold. Though regulated by European directives, lead requires close monitoring due to its environmental persistence and toxicity. METHODS: The first data source was the French surveillance system for monitoring childhood lead poisoning, which records the screening results of children (-18 years), providing data on their temporal and geographical distribution, characteristics, and risk factors. The second data source was Esteban, a cross-sectional study conducted in 2014-2016 on a random sample of the French population as part of the human biomonitoring program. The Esteban lead study concerns 904 children (6-17 years) and 999 adults (18-74 years), providing data on biological samples, sociodemographic characteristics, occupational exposure, environmental and dietary factors. RESULTS: The surveillance system highlighted that lead poisoning affected 10% of children screened between 2015 and 2018. The main risk factor remains housing. Esteban confirmed this observation, finding a general mean of blood lead level (BLL) at 9.9 and 18.5 µg/L for children and adults, respectively. In children, parents' occupation increased BLLs. In adults, the greatest exposure factors were smoking, age, place of residence, alcohol, bread-based products, and homegrown livestock products. In both, drinking tap water and year of housing construction increased BLLs. CONCLUSIONS: The surveillance system showed a high number of children with lead poisoning despite the implementation of prevention measures, which mainly concern lead paints in old and degraded homes. To help identify children at risk, healthcare providers need to know about exposure from housing and the emerging sources identified in the Esteban survey. Despite lower BLLs, the well-known risk factors of lead exposure persist, meaning prevention efforts must continue in order to limit their impact on the population.

'As safe as houses; the risk of childhood lead exposure from housing in England and implications for public health'.

BACKGROUND AND AIM: Exposure to lead can harm a child's health, including damage to the nervous system, delayed growth, hearing loss, and many other adverse health effects, as well as implications for social, economic, educational and social well-being. Lead exposure in children is still a concern and cases require public health management to find the exposure source and interrupt the exposure pathway. Housing characteristics can indicate the presence of lead-contaminated paint and leaded water supply pipes. We aimed to explore the relationship between housing characteristics and elevated blood lead concentration (BLC) in children in England. METHODS: We used a retrospective cohort design and included all cases of lead exposure in children reported to the UK Health Security Agency between 2014 and 2020 via surveillance. A case was a child aged under 16 years, resident in England, BLC of ≥ 0.48 µmol/L (10 µg/dL) and referred for public health management. We collected case demographic details and housing characteristics (age and type). We explored associations between elevated BLC and risk factors, using generalised linear mixed effects models and compared cases' housing type to that expected nationally. RESULTS: Two hundred and sixty-six out of 290 cases met the case definition. There was no difference in BLCs between genders, age groups, deprivation, and housing type. After adjusting for reporting source, housing age and type, cases residing in housing built pre-1976 had a BLC of 0.32 (95%CI 0.02, 0.63) µmols/L (6.63 (95%CI 0.42, 13.0) µg/dL) higher than cases living in housing built after this time. Cases were 1.68 times more likely to be living in terraced housing (housing adjoined to one another) than other children and less likely to live in apartments and detached properties. CONCLUSION: This study suggests an association between housing characteristics and BLC in children. Housing age and type may act as a proxy for lead exposure risk through exposure to leaded paint, lead water pipes, and lead contaminated dust from indoor and outdoor sources. Public health action should consider targeting families more at risk in older housing by raising awareness of the potential presence of lead pipes and paint. Interventions should include working with wider stakeholders including other housing and environmental professionals, the private sector, as well as parents and carers.

Louis Tanquerel des Planches (1810-1862) and the history of discovering lead poisoning in the nervous system.

Louis Tanquerel des Planches (1810-1862) only left us with one significant medical work, his Traité des maladies de plomb ou saturnines (treatise on lead or saturnine diseases), published in 1839. The work served as a reference for diagnosing and treating lead poisoning throughout the second half of the nineteenth century. The word "encephalopathy" that he coined at that time referred to toxic damage to the central nervous system. Whereas for two millennia and for most physicians, lead poisoning was considered lead colic, i.e. paroxysms of abdominal pain, Tanquerel collected seventy-two observations of damage to the central nervous system in workers exposed to lead in Parisian workshops (which no longer exist). He then inventoried and described forms of paralysis, delirium, coma, and convulsions related to lead poisoning. Having no qualms about stepping away from La Charité Hospital where he had treated patients with lead poisoning, he inspected their workplaces and unambiguously presented the deplorable conditions that caused so many patients to die. His "preservative" advice was an initial attempt at medical-social prophylaxis with the goal of helping the working class exposed in workshops without any respect for human life. With support from chemists and pharmacists, Tanquerel showed the presence of lead in brain tissue and thus demonstrated its neurological toxicity as early as 1839. This article is also an opportunity to note the contributions on this topic of some other physicians: François-de-Paule Combalusier (1713-1762), François Victor Mérat de Vaumartoise (1780-1851), Jean-Louis Brachet (1789-1858), Auguste Mirande (1802-1865), Vincent Nivet (1809-1893), Augustin Grisolle (1811-1869), and Ferdinand de Bernard de Montessus (1817-1899).

Environmental assessment of pediatric Lead exposure in Tehran; a prospective cross-sectional study.

BACKGROUND: Ingestion and inhalation are common routes of exposure for lead in humans. Developing countries still have unacceptably high rates of lead toxicity, especially in children. Studies on probable risk factors of lead poisoning in Iranian children are insufficient. In this study, we aimed to evaluate possible environmental factors in children with high blood lead concentrations living in Tehran and neighboring cities. METHODS: In a prospective cross-sectional study between March 2018 and March 2019 we followed all children referred from two pediatric gastrointestinal clinics with blood lead level (BLL) > 5 µg/dL in metropolitan Tehran to investigate possible environmental risk factors in their home. Household specimens including scratched wall paint, house floor dust, windowsill dust, tap water, and consumed spice were evaluated using atomic absorption method to detect lead concentrations. Epidemiological and environmental data collected through in-depth interviews with parents/guardians. Industrial areas were defined based on municipality maps on industrial places. RESULTS: Thirty of 56 parents/guardians with BLL > 5 µg/dL agreed to be followed through environmental investigation. The only categorical statistically significant risk factor was a history of lead poisoning in the family and living in an industrial zone. There was a positive correlation between BLL and interior windowsills dust lead level, r = 0.46, p = 0.01. Scratched paint lead level and BLL showed a significant positive correlation, r = 0.50, p = 0.005. House floor dust lead level (median = 77.4, p < 0.001) and interior windowsill dust lead level (median = 291, p = 0.011) were both significantly higher than the environmental protection agency (EPA) standards of 40 µg/ft2, 250 µg/ft2. Interior windowsill dust lead concentrations were significantly higher in industrial areas (p = 0.026). CONCLUSION: Children's playing environment should be cleaned more often to reduce dust. Moreover, specific rules may need to be implemented for paint lead concentrations and air pollution, especially in industrial areas.

[Lead poisoning associated with an Indian-manufactured unauthorized dietary supplement].

We report the case of a patient with lead poisoning caused by a dietary supplement. A 40-year-old man was referred to us due to intermittent upper abdominal pain and normocytic anemia. His hemoglobin level was 9.3 g/dl, with basophilic stippling in 2.8% of red blood cells. Bone marrow aspirate smear showed ringed sideroblasts that represented 19% of the erythroblasts. The patient reported the use of an unauthorized, Indian-manufactured dietary supplement and was diagnosed with lead poisoning based on a significantly high blood lead level. The dietary supplement was discontinued, and he was successfully treated with lead chelation therapy, and his hemoglobin level normalized within 2 months.

Lead poisoning from Ayurvedic treatment: a further case.

PURPOSE: We report a case of a 30 years old Indian sailor with microcytic anemia (Hb 9.9), persistent abdominal pain, emesis, dark stool, hyperchromic urine, latent jaundice and asthenia. Lead intoxication was confirmed (blood lead value of 102 µg/dL). The patient assumed Ayurvedic medicines in the previous months. Ayurveda is an ancient form of Indian traditional popular medicine aiming to re-establish health and body function through herbal preparations, heavy metals are often added. Our purpose was to treat the patient and to establish the source of poisoning. METHODS: After testing blood and urine lead concentration of other 3 crew members and analyzing over than 150 products used on the ship professional exposure was excluded. We analyzed the two Ayurvedic drugs assumed by the patient with an Inductively Coupled Plasma Mass Spectrometry. The patient underwent three chelation cycles with Calcium Disodium Ethylenediaminetetraacetic acid (EDTA) while monitoring blood and urinary lead levels. RESULTS: The final blood lead level at discharge, after three chelation cycles, was 36.27 µg/dL. One of the two drugs contained extremely high concentrations of lead and mercury. The three different mixtures of this preparation showed lead concentrations of 12,638.54 mg/kg (Sample 2A), 23,043.02 mg/kg (Sample 2B), 21,352.97 mg/kg (Sample 2C); these levels are much higher than the highest values reported in literature for the indian soil (32 mg/kg). CONCLUSIONS: This case and similar cases raise the safety alert on complementary and alternative medicines; Ayurvedic medicine users should be carefully informed about potential risks and signs of poisoning.

Encephalopathy following ingestion of Lead-contaminated opium; magnetic resonance imaging findings.

BACKGROUND: Encephalopathy is an uncommon but serious presentation of lead toxicity. OBJECTIVE: We aimed to determine and follow-up the brain magnetic resonance imaging (MRI) abnormalities in the patients with lead encephalopathy due to ingestion of lead contaminated opium. METHODS: In a cross-sectional study during lead-contaminated opium outbreak, all lead-poisoned patients with any signs/symptoms of encephalopathy were included. RESULTS: Of 19 patients with lead encephalopathy, five died early and other five could not be sent to MRI during their hospitalization period. Mean age was 51 ± 11 years and males were dominant (89%). Median [IQR] blood lead level (BLL) was 101 [81, 108] µg/dL (range; 50 to 200 µg/dL). There was no correlation between MRI findings and signs/symptoms. MRI was normal in six and abnormal in three. Bilateral symmetric involvement of parieto-occipital lobes was observed. Gray matter, gray-white matter junction, and subcortical white matter were also affected. Follow-up MRI was performed in two with abnormal MRI which showed complete and near complete resolution of the abnormalities after cessation of opium use and treatment. CONCLUSION: There was no correlation between MRI findings and BLL. Complete recovery of brain MRI lesions was detected after cessation of opium use.

Chronic lead poisoning induced abdominal pain and anemia: a case report and review of the literature.

BACKGROUND: Chronic lead poisoning (CLP) is a rare cause of abdominal pain and is common in young children, in whom the incidence is higher than it is in adults. As the symptoms of CLP are nonspecific, misdiagnoses or missed diagnoses often occur, especially in sporadic cases. CASE PRESENTATION: We report a 28-year-old young man who was misdiagnosed with renal colic due to sudden acute abdominal pain. After a detailed medical history and physical examination, other possible causes were excluded, CLP was finally diagnosed, and he recovered after chelation treatment. CONCLUSION: Abdominal pain is a very common clinical symptom in adults, which has many causes. We should be vigilant against chronic poisoning, especially CLP. Detailed diagnosis and physical examination are crucial in early diagnosis and treatment.

Long-term simulation of lead concentrations in agricultural soils in relation to human adverse health effects.

Lead (Pb) exposure of consumers and the environment has been reduced over the past decades. Despite all measures taken, immission of Pb onto agricultural soils still occurs, with fertilizer application, lead shot from hunting activities, and Pb from air deposition representing major sources. Little is known about the intermediate and long-term consequences of these emissions. To gain more insight, we established a mathematical model that considers input from fertilizer, ammunition, deposition from air, uptake of Pb by crops, and wash-out to simulate the resulting Pb concentrations in soil over extended periods. In a further step, human oral exposure by crop-based food was simulated and blood concentrations were derived to estimate the margin of exposure to Pb-induced toxic effects. Simulating current farming scenarios, a new equilibrium concentration of Pb in soil would be established after several centuries. Developmental neurotoxicity represents the most critical toxicological effect of Pb for humans. According to our model, a Pb concentration of ~ 5 mg/kg in agricultural soil leads to an intake of approximately 10 µg Pb per person per day by the consumption of agricultural products, the dose corresponding to the tolerable daily intake (TDI). Therefore, 5 mg Pb/kg represents a critical concentration in soil that should not be exceeded. Starting with a soil concentration of 0.1 mg/kg, the current control level for crop fields, our simulation predicts periods of ~ 50 and ~ 175 years for two Pb immission scenarios for mass of Pb per area and year [scenario 1: ~ 400 g Pb/(ha × a); scenario 2: ~ 175 g Pb/(ha × a)], until the critical concentration of ~ 5 mg/kg Pb in soil would be reached. The two scenarios, which differ in their Pb input via fertilizer, represent relatively high but not unrealistic Pb immissions. From these scenarios, we calculated that the annual deposition of Pb onto soil should remain below ~ 100 g/(ha × a) in order not to exceed the critical soil level of 5 mg/kg. We propose as efficient measures to reduce Pb input into agricultural soil to lower the Pb content of compost and to use alternatives to Pb ammunition for hunting.

Adult lead exposure from ammunition reloading and indoor residential shooting.

The use and maintenance of firearms is a common and often preventable source of adult lead exposure that is often poorly understood by medical professionals. This case describes an elevated blood lead level (BLL) in an adult man due to the exposure sources of ammunition reloading and indoor target shooting in the basement of his home and details the challenges involved in the diagnosis and management of such cases. The elevated BLL was reduced through strict attention to personal hygiene during the reloading process and while shooting, improved ventilation and cleaning of the basement, and avoidance of vacuuming and use of dry cleaning techniques. Medical providers may be unfamiliar with the risks of indoor residential shooting and how to ameliorate them; this knowledge deficit may result in delays in diagnosis as well as an inability to successfully mitigate the risks for exposure. Time-sensitive diagnosis and treatment, comprehensive risk assessments, and reduction of exposure sources are important facets in the care of adult patients who are exposed to lead through recreational activities. Health care professionals should be aware of the potential dangers of ammunition reloading and indoor shooting, be familiar with ways to reduce lead exposure during these activities, and understand the resources that are available for the management of lead-exposed patients.

Characteristics of Pediatric Patients With Retained Bullet Fragments and Need for Follow-Up Blood Lead Monitoring.

OBJECTIVES: Multiple case reports of lead toxicity related to retained bullet fragments in pediatric patients sustaining gunshot wound have been published. The purpose of the present study was to determine whether the demographic and clinical characteristics of gunshot wounds (GSWs) could be classified high/low risk and whether routine blood lead monitoring is necessary in these patients. METHODS: A single-center prospective case series of pediatric GSW patients presenting to the emergency department (ED). The data points that were collected and analyzed included age, sex, race, wound location, disposition, and baseline and follow-up lead levels within 6 months post-injury. RESULTS: Twenty patients were enrolled in the study and the median age was 7.5 years (interquartile range 5.25-10.75); 75% of the patients were African American. A total of 15 patients (75%) had injuries in either a lower or upper extremity, 9 of whom required admission. Almost all of the injuries involving the head, chest, or abdomen required admission. Of the patients, 65% were admitted and 35% were discharged. All of the patients had an initial blood lead level taken, and follow-up lead levels were determined at 6 months post-injury to be <5 µg/dL. Twelve of 20 patients were lost to follow-up. CONCLUSIONS: Pediatric GSW is common in male African Americans and these patients had baseline and follow-up lead levels below the reference level. These patients were difficult to follow up. Based on the available data, follow-up lead monitoring may not be indicated.

Opium-Related Lead Toxicity: An Integrative Review and Case Series.

BACKGROUND: Restrictive regulations and the increased price of opioids have resulted in the addition of impurities to illicit opioids by drug dealers. Among the adulterants, lead salts are optimal agents to make packages heavier. Consequently, lead toxicity has emerged in the opioid-user population. OBJECTIVES: Our goal was to review the related literature and describe patients with common presentations of opioid-related lead poisoning to provide a basis to prepare optimal management. METHODS: A narrative review was performed aiming to study opioid lead poisoning. PubMed and Google Scholar databases were explored with two Medical Subject Heading terms, lead poisoning and substance-related disorders to find a broad but relevant spectrum of articles. Then, the reference lists within those articles were checked to upgrade our literature pool on this issue. RESULTS: Ultimately, among English-language articles, 16 were case series and case reports of patients with lead intoxication after opioid consumption. Data pertaining to disease characteristics, diagnosis, and treatment protocols were extracted. CONCLUSIONS: The clinical presentation of opioid lead intoxication can vary from rather asymptomatic to severely debilitating gastrointestinal or neurologic symptoms. The diagnosis is made by checking lead blood levels after obviating other critical diagnoses and should be considered in each drug user in endemic regions of opioid addiction, such as the Middle East. Management protocols are suggested to cover both features of opioid-related complications and lead toxicity.

Challenges in diagnosing lead poisoning: A review of occupationally and nonoccupationally exposed cases reported in India.

Lead is a nonessential metal which enters the body through various means and is considered as one of the most common health toxins. Several cases of lead poisoning are reported as a result of inhalation or ingestion of lead in employees working as painters, smelters, electric accumulator manufacturers, compositors, auto mechanics, and miners. In addition to occupational lead exposure, several cases of lead poisoning are reported in the general population through various sources and pathways. Innumerable signs and symptoms of lead poisoning observed are subtle and depend on the extent and duration of exposure. The objective of this review article is to discuss occupationally and nonoccupationally exposed lead poisoning cases reported in India and the associated symptoms, mode of therapy, and environmental intervention used in managing these cases. Lead poisoning cases cannot be identified at an early stage as the symptoms are very general and mimic that of other disorders, and patients might receive only symptomatic treatment. Knowledge about the various symptoms and potential sources is of utmost importance. Medical practitioners when confronted with patients experiencing signs and symptoms as discussed in this article can speculate the possibility of lead poisoning, which could lead to early diagnosis and its management.

Participation of phospholipase-A2 and sphingomyelinase in the molecular pathways to eryptosis induced by oxidative stress in lead-exposed workers.

The increment of eryptosis in lead-exposed workers has been associated with oxidative stress, having as the main mediator [Ca2+]i. However, other molecules could participate as signals, such as PLA2 and SMase, which have been proposed to increase PGE2 and ceramides, both involved in the increment of PS externalization due to osmotic stress. To study the role of these enzymes in lead intoxication, we studied 30 lead exposed workers and 27 non-lead exposed individuals. We found, compared to non-exposed subjects, lead intoxication characterized by high blood lead concentration (median = 39.1 µg/dL), and low δ-ALAD activity (median = 348 nmol of porphobilinogen/h/mL); oxidative stress with high lipid peroxidation (median = 1.31 nmol of malondialdehyde/mL) and low TAC (median = 370 mM Trolox equivalents); a higher enzymatic activity of PLA2 (median = 518 AFU/mg) and SMase (median = 706 AFU/mg) and higher eryptosis (median = 0.92% PS externalization). Correlation and conditional probability analyses permit to associate oxidative stress and eryptosis with high PLA2 activity. However, high SMase activity was only associated with PLA2 activity. The role of these enzymes in the signal path to eryptosis induced by oxidative stress in lead-exposed workers is discussed.