Occupational Poisoning Research Articles

Occupational lead poisoning: Can it be eliminated?

The continued occurrence of occupational lead poisoning and overexposure in the United States represents a serious challenge to the occupational health community. We outline a proposed action strategy which integrates case-based surveillance, hazard surveillance, increased requirements for biological monitoring, and targeted educational activities, with a goal of eliminating occupational lead poisoning. The system provides a simple mechanism for monitoring compliance in lead-using employers, in order to identify employers for enforcement action. Lead poisoning should be viewed as an eradicable condition; successfully solving the persistent lead overexposure problem can serve as a model for approaching other occupational diseases.

Occupational lead poisoning: Who should conduct surveillance and training?

This commentary challenges the current employer-controlled model for delivering occupational health services. Problems emanating from traditional employer-based medical surveillance and worker education programs for occupational lead poisoning are identified. A new public health model for delivering these services is proposed. This model utilizes a case-based and hazard-based method for bringing workplaces and employers into the program and features direct delivery of surveillance and training services by public health agencies.

Pesticide poisonings in Costa Rica.

A descriptive epidemiologic study, conducted in Costa Rica, investigated the incidence of pesticide poisonings with special attention to agricultural workers and occupational exposure. Information from three national registers (occupational accident and disease reports, hospitalizations, and deaths) were used. During 1986, 1800 occupational accidents caused by pesticides were reported; between 1980 and 1986 altogether 3330 persons were hospitalized and 429 died. Cholinesterase inhibitors caused 71% of the reported occupational accidents, 63% of the hospitalizations, and 36% of the deaths. Paraquat caused 21% of the occupational accidents, 24% of the hospitalizations, and 60% of the deaths. Hospitalizations and deaths were 13 and 11 times, respectively, more frequent among agricultural workers than among the rest of the population. High-risk groups for occupational poisonings included agricultural workers aged 15-29 years, female workers, and banana plantation workers. The yearly incidence of symptomatic occupational pesticide poisonings among agricultural workers was estimated at 4.5%.

Fouling one's own nest revisited

Transport of hazards from the workplace to the home by workers is a previously recognized but poorly addressed public health problem. Particularly disturbing are the childhood intoxications which may result from such paraoccupational exposure. Work clothes and shoes appear to be a common vehicle for hazard transport in recently reported cases as they were in the past, although other "markers" for potential paraoccupational exposure may be derived from case reviews. These include: poor workplace hygiene, occupational intoxications in adult workers, and the "cottage industry" phenomenon. These markers are reviewed in the context of recently reported cases and strategies are suggested to mitigate these easily preventable exposures.

Etiology of intoxication: a study of 557 cases.

Our results were obtained from the emergency service at Elche General Hospital, which covers an adult population of 275,076 inhabitants. We studied intoxicated patients aged 15 years and above, during 1988. Our aim was to investigate the etiological and epidemiological circumstances of intoxications. We obtained a prevalence of voluntary cases (61.6%) over accidental cases (38.3%), with self-poisoning being more frequent than drug addiction, in the first group and animal stings being more frequent than domestic or occupational intoxication in the second. Mortality resulted in 1.6% of cases; the etiology of the highest mortality was self-poisoning and the most common toxic substances were caustic substances.

Quality assurance in the biological monitoring of lead exposure in China

Based on the statistical data of the nationwide occupational diseases reporting in 1986-1988, lead poisoning stood the first place of chronic occupational poisonings in China. Biological monitoring of lead exposure is of paramount importance in both occupational and environmental health. In order to ensure lead testing data valid enough for taking actions of prevention and control, a quality assurance scheme including selection of reliable analytical techniques, establishing reference laboratory, application of standard reference materials, and conducting internal and external quality control program was implemented in China. Since the rigid assurance procedure was conducted during studies on "background levels of lead in non-exposure population" and "revision of the diagnostic criteria for lead", compatible and reliable results were obtained.

A study on the mercury contamination sources and risk for occupational mercury poisoning of mercury exposed workers in Korea

A study on the mercury contamination sources and risk for occupational mercury poisoning of mercury exposed workers in Korea

Targeting of workplace inspections for lead

The prevention of occupational lead poisoning requires identification of worksites with ongoing excessive lead exposures. The utility of different sources of surveillance data in identifying worksites was evaluated by comparing a list of companies inspected by the Occupational Safety and Health Administration (OSHA) for lead with 1) Ohio Bureau of Workers' Compensation (BWC) claims for lead poisoning, and 2) the New York Health Department's Heavy Metal Registry (NYHMR) reports of individuals with elevated blood lead levels. For the period 1981 through 1985, the NYHMR identified 179 companies with at least one employee having an elevated blood lead level. Of the 134 OSHA inspections conducted in New York during the same time period, 23 (17%) companies were identified by the NYHMR. In Ohio from 1979 through 1985, 50 companies had workers' compensation claims filed against them involving documented elevated blood lead levels. OSHA inspected 306 companies; 23 (7.5%) were identified by the BWC. In both states, companies inspected by OSHA were concentrated in larger industries with traditional, well-recognized lead hazards (e.g., primary metal and fabricated metals). Companies identified by compensation claims and laboratory reports tended to be in industries dominated by smaller establishments where lead is not a primary part of the industrial process (e.g., automotive repair and construction). Sources of surveillance data, such as workers' compensation claims and laboratory reports, identify worksites that tend not to be routinely inspected by OSHA and which need intervention to prevent excessive lead exposure. To maximize the impact of public health resources devoted to the elimination of occupational lead poisoning, follow-up efforts at companies identified by state health departments and workers' compensation systems offer an important opportunity to complement OSHA's inspection efforts.

Environmental and biological monitoring for lead exposure in California workplaces.

Patterns of environmental and biological monitoring for lead exposure were surveyed in lead-using industries in California. Employer self-reporting indicates a large proportion of potentially lead-exposed workers have never participated in a monitoring program. Only 2.6 percent of facilities have done environmental monitoring for lead, and only 1.4 percent have routine biological monitoring programs. Monitoring practices vary by size of facility, with higher proportions in industries in which larger facilities predominate. Almost 80 percent of battery manufacturing employees work in job classifications which have been monitored, versus only 1 percent of radiator-repair workers. These findings suggest that laboratory-based surveillance for occupational lead poisoning may seriously underestimate the true number of lead poisoned workers and raise serious questions regarding compliance with key elements of the OSHA Lead Standard.

Chronic neuropsychological sequelae of occupational exposure to organophosphate insecticides

The early (immediate and delayed) neurotoxic effects of acute organophosphate intoxication are well documented in the scientific literature; lack of recognition and inappropriate treatment of occupational poisonings continue. Less well understood is the potential development of chronic neuropsychological sequelae from exposures to insecticides. We undertook two cohort studies to assess chronic neuropsychologic effects of insecticide poisoning. Based, in part, on our clinical evaluation of several patients, these studies included: 1) a retrospective cohort study assessing function at least 1 year following moderate to severe poisonings among farm workers; and 2) a prospective cohort study assessing neuropsychological function before and after a season of organophosphate exposures among pesticide applicators. A typical case description, the study design, methodologic problems, and preliminary findings of these ongoing studies are presented.

Clinical evaluation on 5 cases of lead Poisoning

5 cases of lead poisoning were investigated clinically. Of the 5 patients, 4 were male and 1 was female. The causes of lead poisoning in 3 cases were ingestion of herb drug pills and in 2 cases were occupational poisoning. Chief complain at admission in 4 cases were in defined colicky abdominal pain and constipation. Only 1 case complained of dizziness and palpitation without gastrointestinal symptom. On peripheral blood, normocytic normochromic anemia (mean Hgb 9.2gm/dl), reticulocytosis (mean 4.7%) and basophilic stippling were found in 100% of patients. Bone marrow aspiration was done in 4 cases. Erythroid hyperplasia and basophilic stippling were found in all 4 cases. Mean M : E ratio was 0.7 : 1. The lead concentration in serum was in creased in 4 cases (80%) of patients. Lead concentration, deltaaminolevulinic acid concentration in 24 hours collected urine were in creased in 5 patients (100%). Qualitative test of coproporphyrin of urine was positive in all 5 cases. 3 patients treated with Ca-EDTA, abdominal pain was improved rapidly and hemoglobin level was in creased slowly.

The psychological performance profile in occupational intoxications

Research of the last decades has yielded information about behavioral changes in workers exposed to neurotoxic chemicals and in patients with occupational intoxications. However, the existing documentation does not provide a detailed neuropsychological description of the toxic syndrome. A comparison of the performances of patients with intoxications due to lead, carbon disulphide and organic solvents indicated some differences in the three neurobehavioral syndromes. In the lead intoxication the effect was rather general, whereas psychomotor retardation was the most prominent feature in the carbon disulphide intoxication, and cognitive disturbance in the solvent intoxication. On the other hand, a follow-up of organic solvent patients indicated that the syndrome caused by organic solvents is not static, but changes do occur after cessation of the exposure: most often improvement of cognitive functions, with the exception of the memory, and further retardation of psychomotor speed. The behavioral changes and their prognosis show, however, considerable individual variation, due to the variation of the premorbid ability structure and personality, and to variation of the exposure history.

Treatment of occupational lead poisoning by slow subcutaneous administration of CaNa 2 EDTA

Treatment of occupational lead poisoning by slow subcutaneous administration of CaNa 2 EDTA

Agrochemical poisoning in Sri Lanka

Mortality resulting from agrochemicals met within the Office of the Judical Medical Officer, Colombo, which is the premier Medico-legal Institute in Sri Lanka, are analysed over a 3-year period and the morbidity and mortality rates of the entire country are examined over a 10-year period. The number of patients admitted to hospitals in Sri Lanka during the period 1975–1983, stood at around 11 000–15 000 each year, with the year 1983 recording 16 649 admissions. The number of deaths during the same period varied from 900 to 1500 each year, while the year 1983 recording 1521 deaths. About 75% of such cases of poisoning were due to self ingestion while accidental and occupational poisoning formed the balance. Principal agricultural districts like Kurunegala, Jaffna, Vavuniya, Nuwara-Eliya and Badulla recorded the highest incidence of poisoning. The mortality figures of the Office of the J.M.O., Colombo, indicated that 4% of all bodies subjected to autopsy were those of agrochemical poisoning. The male/female ratio was 2:1. Seventy-five percent of deaths from agrochemical poisoning were recorded in the 15–39 year age group, while 33% of deaths belonged to the 20–24 age group. One third of cases of agrochemical poisoning were dead on being brought to hospital, while 50% were dead within 2 h and 60% dead within 24 h. Organophosphates accounted for 57.6% of all cases of agrochemical poisoning, while paraquat accounted for 21.2% of cases. Deaths were also reported from what are called safe chemicals like Carbamates and Pyrethrums due to their lethal additives.

Correlation Between Biochemical Indicators of Lead Exposure and Semen Quality in a Lead-Poisoned Firearms Instructor

LEAD poisoning is a disease of great public health concern, particularly because of the hazards that lead can pose to children as a result of ingestion of lead-based paint and perhaps as a consequence of the effects of lead pollution of the ambient air.¹ However, lead poisoning is also a common occupational disease among adults.²Groups at high risk of developing this disorder include smelter workers,³workers engaged in flame cutting of lead-painted iron and steel structures,⁴and arts and craft workers. Persons who work as instructors at indoor firing ranges are likewise at high risk for occupational lead poisoning.⁵The typical biochemical features of lead poisoning include inhibition of heme synthesis manifested by elevated levels of erythrocyte protoporphyrin (free erythrocyte protoporphyrin and zinc protoporphyrin [ZPP]) and decreased activity of δ-aminolevulinic acid dehydratase.^6,7Common symptoms are nonspecific neurologic symptoms (eg, headache, dizziness, fatigue, and sleep

Sensitivity to tri-o-cresylphosphate neurotoxicity on n-hexane exposed hens as a model of simultaneous hexacarbon solvent and organophosphorus occupational intoxication.

Hens were given a single oral dose (0.235 mg/kg) of tri-o-cresylphosphate (TOCP) during chronic n-hexane treatment (200 mg/kg daily, 5 days/week). They were compared with other animals treated only with n-hexane or only with TOCP. Animals treated with a higher TOCP dose (1 ml/kg) were used as positive controls. The animals treated with both n-hexane and TOCP showed rapid development of severe ataxia. The rate of the ataxia development was similar to that of the positive controls but with earlier onset of the first signs and with less loss of body weight. However, animals treated only with n-hexane, under the same conditions, showed only reversible weakness and sedative effects, and those treated only with TOCP showed slow and slight ataxia development. The n-hexane- and TOCP-treated hens showed axonal swelling with myelin retraction associated with Ranvier's nodes, which is characteristic of long hexacarbon exposure. Some internodal swellings were also observed but less frequently than the paranodal swellings. The time course of the ataxia development was similar to an organophosphorus-induced delayed neuropathy (OPIDN); however, the light microscopy observation more closely resembled hexacarbon neuropathy. The results suggest a potentiation effect of n-hexane and TOCP neurotoxicities which could be related to some human occupational neuropathies.

Occupational lead poisoning in Ohio: surveillance using workers' compensation data.

To determine the utility of workers' compensation (WC) data in a system for the surveillance of occupational lead poisoning, we reviewed workers' compensation claims for lead poisoning in Ohio. For the period 1979 through 1983, 92 (81 per cent) of the 114 claims attributed to lead met our case definition of lead poisoning. The likelihood that a company had a case of lead poisoning was strongly correlated with the number of claims against the company. Thirty companies accounted for the 92 cases; two companies accounted for 49 per cent of these. Inspection by the Occupational Safety and Health Administration (OSHA) occurred at 14 of these companies, all of which were cited for violations of the OSHA lead standard. Comparison of the Standard Industrial Classification (SIC) codes for the 14 companies inspected by OSHA with the 15 companies not inspected by OSHA revealed that OSHA inspected battery manufacturers, non-ferrous foundries, secondary smelters, and primary lead smelters, but not bridge painters, manufacturers of electronic components, mechanical power transmission equipment, pumps, and paints, nor a sheriff's office where firing range slugs were remelted to make new bullets. Neither the number of cases of lead poisoning at a company nor the size of a company was related to the likelihood of being inspected by OSHA. Claims for WC appear to be a useful adjunct to an occupational lead poisoning surveillance system; their usefulness should be compared to that of other systems such as laboratory reports of elevated blood lead levels in adults.

HBsAg antiHBs and liver function tests in lead-exposed workers.

In Taiwan, an endemic area of hepatitis B virus (HBV) infection, occupational lead poisoning is a major problem of industrial hygiene. In order to estimate the prevalence of HBV infection and the effect of lead on liver function in lead-exposed workers, we determined the prevalence of hepatitis B surface antigen (HBsAg) and its antibody (antiHBs), measured blood lead and urinary coproporphyrin levels, hematocrit and conventional liver function tests (LFT) in 98 lead-exposed workers and 63 healthy controls. The results demonstrated that the blood lead concentration, urinary coproporphyrin excretion are significantly higher in the workers than in the controls, whereas the hematocrit level is statistically lower in the workers than in the controls. The prevalent rates of HBsAg (30.61%) and antiHBs (63.27%) in the workers showed no significant difference from the rates (20.63% and 74.60%, respectively) in healthy subjects. Among the liver function tests, GOT, GPT, alkaline phosphatase, total protein, globulin and alpha-1 globulin in workers are statistically higher than in controls, but A/G, total and direct bilirubin are significantly lower in the former than in the latter. Among workers, there is no relationship between different blood lead or urinary coproporphyrin concentration and the prevalence of HBsAg and antiHBs, but blood lead concentration is significantly higher in workers with HBsAg-positive than those with antiHbs-positive. The cause is to be determined.

Twenty-five years of behavioral toxicology within occupational medicine: a personal account.

Decisive for my long-term involvement in behavioral toxicology were the hours spent in interviewing and testing patients with occupational poisonings during the first years of my career as a clinical psychologist within the framework of occupational medicine. Important auxiliary factors were the innovative and inspiring scientific climate at our Institute, and the supportive kind of scientific education provided by this environment during the years. It has been rewarding and exciting to follow the international progress of behavioral toxicology. Advances in this special domain of research were and are partly related to advances in occupational epidemiology and toxicology, in neurotoxicology and other allied disciplines, as well as to advances in other branches of psychology. But the major challenge to behavioral toxicology during the first decades of its existence has been finding its place and role within these disciplines. Important challenges for the next decades are defining further the exposure-effect relationships as a basis for the standard setting, extending the surveillance of neurotoxic hazards to the developing countries, and searching for better understanding of the practical significance o neurobehavioral effects, eg, from the point of view of the afflicted individual. To realize these aims, further efforts are needed to coordinate the field of behavioral toxicology and to augment communication between those immediately involved.

Occupational lead exposure, acute intoxication, and chronic nephropathy: Report of a case and review of the literature

Occupational lead exposure, acute intoxication, and chronic nephropathy: Report of a case and review of the literature