Intervention to reduce heat stress and improve efficiency among sugarcane workers in El Salvador: Phase 1.

BACKGROUND: Chronic heat stress and dehydration from strenuous work in hot environments is considered an essential component of the epidemic of chronic kidney disease in Central America. OBJECTIVE: (1) To assess feasibility of providing an intervention modelled on OSHA's Water.Rest.Shade programme (WRS) during sugarcane cutting and (2) to prevent heat stress and dehydration without decreasing productivity. METHODS: Midway through the 6-month harvest, the intervention introduced WRS practices. A 60-person cutting group was provided water supplied in individual backpacks, mobile shaded rest areas and scheduled rest periods. Ergonomically improved machetes and efficiency strategies were also implemented. Health data (anthropometric, blood, urine, questionnaires) were collected preharvest, preintervention, mid-intervention and at the end of harvest. A subsample participated in focus group discussions. Daily wet bulb globe temperatures (WBGT) were recorded. The employer provided individual production records. RESULTS: Over the harvest WBGT was >26°C from 9:00 onwards reaching average maximum of 29.3±1.7°C, around 13:00. Postintervention self-reported water consumption increased 25%. Symptoms associated with heat stress and with dehydration decreased. Individual daily production increased from 5.1 to a high of 7.3 tons/person/day postintervention. This increase was greater than in other cutting groups at the company. Focus groups reported a positive perception of components of the WRS, and the new machete and cutting programmes. CONCLUSIONS: A WRS intervention is feasible in sugarcane fields, and appears to markedly reduce the impact of the heat stress conditions for the workforce. With proper attention to work practices, production can be maintained with less impact on worker health.

TICAREX: Exposiciones laborales a agentes cancerígenos y plaguicidas en Costa Rica / TICAREX: occupational exposure to carcinogens and pesticides in Costa Rica

El sistema europeo de datos CAREX (CARcinogen Exposure) considera la fuerza laboral de un país agrupada en 55 sectores económicos según la Clasificación Internacional de Actividades Económicas de las Naciones Unidas, segunda revisión de 1968, y mediante la aplicación de proporciones de trabajadores expuestos a partir de datos generados en estudios de higiene industrial para 139 agentes carcinógenos, los convierte en fuerza laboral expuesta y número de trabajadores expuestos a agentes carcinogénicos, según rama de actividad. En este artículo se describe una modificación y extensión del sistema CAREX para calcular los números de trabajadores expuestos a agentes cancerígenos y plaguicidas en Costa Rica. Esta primera aplicación de CAREX fuera de Europa (TICAREX) fue realizada en Costa Rica, Centroamérica, para 27 agentes cancerígenos y 7 grupos de plaguicidas, considerados de interés para el país, realizando estimaciones por separado para mujeres y hombres. Los agentes cancerígenos más frecuentes a los que se expone la fuerza laboral de Costa Rica de 1.3 millones fueron la radiación solar (333,000 trabajadores), las emisiones de diesel (278,000), paraquat y diquat (175,000), el humo de tabaco ambiental (71,000), los compuestos de cromo hexavalente (55,000), el benceno (52,000), mancozeb, maneb y zineb (49,000), clorotalonil (38,000), el polvo de madera (32,000), el cuarzo (27,000), benomil (19,000), el plomo y sus compuestos inorgánicos (19,000), tetracloroetileno (18,000), y los compuestos aromáticos policíclicos (17,000). En los hombres, la distribución se mantuvo muy ajustada a los anteriores rangos, sin embargo en las mujeres, debido a su diferente distribución en los sectores, el formaldehído, el radón y el cloruro de metileno superaron a los plaguicidas, el cromo (VI), el polvo de madera y el cuarzo. La agricultura, la construcción, los servicios personales y domésticos, el transporte terrestre y acuático y los servicios asociados al transporte, la fabricación de productos cerámicos y similares, la manufactura de productos de madera, la minería, la silvicultura, la pesca, la fabricación de maquinaria y aparatos eléctricos, bares y restaurantes fueron sectores de donde las exposiciones son frecuentes. Una reducción drástica de exposiciones laborales y ambientales a estos agentes daría por resultado mejoras sustanciales en los niveles de salud pública y ocupacional. La vigilancia de las exposiciones laborales y de la salud en el trabajo son esenciales para el control de la contaminación y de las exposiciones a los agentes cancerígenos

The European data system CAREX takes the workforce of a country grouped into 55 economic sectors according to the International Economic Activity Classification of the United Nations, the second 1968 revision and through the application of proportions of workers exposed to 139 carcinogenic agents based on data from industrial hygiene studies, converting it into the total workforce exposed to carcinogens by sector. . In this article we describe a modification and extension of of the CAREX system in order to calculate the number of workers exposed to carcinogens in Costa Rica. It is the first use of CAREX outside Europe (TICAREX) in Costa Rica, Central America, for 27carcinogens and 7 groups of pesticides thought to be of interest for the country, with separate estimations for men and women. The most frequent agents of exposure for the 1.3 million workers of Costa Rica were solar radiation (333,000 workers); diesel exhaust (278,000); paraquat and diquat (175,000); environmental tobacco smoke (71,000); hexavalent chromium compounds (55,000); benzene (52,000); mancozeb, maneb and zineb (49,000); chlorothalonil (38,000); wood dust (32,000); quartz (27,000); benomyl (19,000); lead and its inorganic compounds (19,000); tetrachloroethylene (18,000); and polycyclic aromatic hydrocarbons (17,000). Owing to the different occupational distribution between the genders, exposures to formaldehyde, radon and methylene chloride were more frequent than pesticides, hexavalent chromium, wood dust, and quartz in women. Agriculture, construction, personal and domestic services, manufacture of wood products, mining, forestry, fishing, manufacture of electrical products, and bars and restaurants were sectors with frequent exposures. Substantial reduction of occupational and environmental exposures to these agents would significantly improve public and occupational health. Reduction of occupational exposures is usually also followed by improvement of environmental quality. Monitoring of exposures and health of workers and the general public is an essential element in the control of environmental contamination and human exposures

The influence on seeking care because of neck and shoulder disorders from work-related exposures.

The aim of this study was to assess the influence of work-related physical and psychosocial factors on seeking care for neck or shoulder disorders among men and women in a general working population. The study population comprised gainfully employed (>17 hours per week) men and women in the municipality of Norrtälje, altogether 392 cases and 1,511 controls. Cases were defined as persons seeking care because of neck or shoulder disorders by any caregiver in the region. The study began in 1994 and continued to 1997. We assessed physical and psychosocial exposures by questionnaires and interviews. The pattern of seeking care for neck or shoulder disorders differed between men and women. Among men, work with vibrating tools [relative risk (RR) = 1.6], not having a fixed salary (RR = 1.9), and low demands in relation to competence (RR = 1.5) were the strongest risk indicators obtained in analyses stratified for age and previous symptoms. Among women, repetitive hand or finger movements (RR = 1.6), constrained sitting (RR = 1.6), not having a fixed salary (RR = 2.0), and solitary work (RR = 1.8) were the strongest risk indicators. A large proportion of the general population was exposed to several of these moderately harmful conditions, and their concomitant effect may explain the high incidence of neck and shoulder disorders in the general working population.

Experiences from long-term research cooperation between Costa Rican, Nicaraguan, and Swedish institutions.

This paper summarizes experiences from long-term ongoing cooperation between Swedish research institutions and institutions at the National Universities in Nicaragua and Costa Rica. 24 researchers and teachers from the Central American institutions and ten Swedish research students have been trained. In addition to three full doctoral and three licentiate (two-year PhD program) theses, the two programs have so far published 15 articles in English-language, international, refereed journals and about three times as many abstracts for conferences in more than ten countries. A "sandwich" model for training is recommended, where the southern researchers come to the wealthier partner for collaborative analyses and write-ups of the publications, while spending 50-75% of their time in their home countries for data collection. Such collaboration should be planned for a time span of at least eight years and include substantial numbers of researchers and students. Means to minimize the risk of brain drain are suggested. The collaboration has been important for the globalization of the research cultures at the participating institutions and has trained international experts.

A population-based case-referent study of myocardial infarction and occupational exposure to motor exhaust, other combustion products, organic solvents, lead, and dynamite. Stockholm Heart Epidemiology Program (SHEEP) Study Group.

This case-referent study investigated the risk of myocardial infarction from occupational exposure to motor exhaust, other combustion products, organic solvents, lead, and dynamite. We identified first-time, nonfatal myocardial infarctions among men and women 45-70 years of age in Stockholm County from 1992 through 1994. We selected referent subjects from the population to match the demographic characteristics of the cases. A lifetime history of occupations was obtained by questionnaire. The response rate was 81% for the cases and 74% for the referents, with 1,335 cases and 1,658 referents included in the study. An occupational hygienist assessed occupational exposures, coding the intensity and probability of exposure for each subject. We adjusted relative risk estimates for tobacco smoking, alcohol drinking, hypertension, diabetes mellitus, overweight, and physical inactivity at leisure time. The relative risk of myocardial infarction was 2.11 (95% confidence interval = 1.23-3.60) among those who were highly exposed and 1.42 (95% confidence interval = 1.05-1.92) among those who were intermediately exposed to combustion products from organic material. We observed an exposure-response pattern, in terms of both maximum exposure intensity and cumulative dose. Exposure to dynamite and organic solvents was possibly associated with an increased risk. The other exposures were not consistently associated with myocardial infarction.

Time trends of occupational pesticide-related injuries in Costa Rica, 1982-1992.

To evaluate time trends of occupational pesticide-related injuries in Costa Rica, a survey was carried out three times over a ten-year period at a national reporting system for occupational accidents and diseases among wage-earning workers. The sample comprised the accidents reported during the months of June of the years 1982, 1987, and 1992. The overall incidence rates were 1.8, 2.7, and 2.5 per 1,000 agricultural workers, respectively. Rates among female workers increased (3.1, 3.7, 5.4) and were elevated as compared with male workers (1.7, 2.6, 2.3). The trend for topical lesions was upgoing (1.2, 1.4, 2.1), consistent with an increased use of fungicides and lack of safety measures for pesticides with low acute toxicity. Systemic poisonings peaked in 1987 (0.6, 1.2, 0.5), declining in 1992 with increased use of biologic pest control and pyrethroid insecticides less toxic than cholinesterase inhibitors, and improved safety during nematocide applications on banana plantations. In 1992, despite the largest decline of systemic poisonings in the banana-producing Atlantic Region, poisonings as well as topical injuries were still four times more frequent in this region than in the rest of the country. Restriction of highly toxic pesticides together with implementation of occupational safety measures can reduce systemic poisonings in developing countries. Such policies need to be extended to other pesticides to prevent less life threatening but often disabling skin and eye injuries.

Mortality and cancer incidence among Swedish lumberjacks exposed to phenoxy herbicides.

OBJECTIVES: To determine mortality and cancer incidence relative to exposure to phenoxy herbicides. METHODS: A cohort of Swedish lumberjacks of which 261 were exposed to phenoxy herbicides, and 250 were unexposed, was followed up for mortality from 1954 to 1994, and for cancer incidence from 1958 to 1992. The number of days of exposure to phenoxy herbicides was determined from pay slips. With the county population as a reference, standardised mortality ratios and cancer incidence ratios (SMR and SIR) were calculated. RESULTS: Mortality and cancer incidence were low with two exceptions; a small but highly exposed group of foremen showed an increased cancer incidence (SIR 274, 95% confidence interval (95% CI) 100 to 596), and over all mortality (SMR 141, 95% CI 68 to 260). Of three cases of non-Hodgkin's lymphoma, two were found among the most exposed workers. CONCLUSIONS: The results provide some support to claims of previous studies that exposure to phenoxy herbicides might be related to non-Hodgkin's lymphoma and to an increased overall cancer risk.

Primary osteoarthrosis of the knee in men and women as a result of lifelong physical load from work.

OBJECTIVES: This study investigated the effect of lifelong physical load from work on the development of knee osteoarthrosis (OA) leading to prosthetic surgery among men and women. METHODS: In a population-based case-referent study, men and women (N=625) who had had prosthetic surgery due to primary tibiofemoral OA were compared with referents (N=548) as to job titles and exposure to physical load in occupational work, housework, and leisure-time activities from 15 to 50 years of age. RESULTS: Male forestry and construction workers, and both male and female farmers ran the highest risk of knee OA. The men had considerably higher exposure to lifting at work, and also to jumps and vibration, than the women. Among the men there was an association between lifting at work [odds ratio (OR) 3.0, 95% confidence interval (95% CI) 1.6-5.5], squatting or knee bending (OR 2.9, 95% CI 1.7-4.9), kneeling (OR 2.1, 95% CI 1.4-3.3), and jumping (OR 2.7, 95% CI 1.7-4.1) with knee OA. Exposure to physically demanding tasks at home, such as taking care of an elderly or handicapped person, was associated with knee OA among the women (OR 2.2, 95% CI 1.3-3.6). CONCLUSIONS: Working as a farmer or as a construction worker could be associated with the development of knee OA and lead to prosthetic surgery. Men and women differ in the quality and quantity of reported physical load and also in the strength of the risk estimates. A reduction of high physical load at work and at home could probably lower the risk of knee OA later in life.

To what extent do current and past physical and psychosocial occupational factors explain care-seeking for low back pain in a working population? Results from the Musculoskeletal Intervention Center-Norrtälje Study.

STUDY DESIGN: A population-based case referent study. OBJECTIVES: To determine whether current and past physical and psychosocial occupational factors are associated with care-seeking for low back pain in working men and women. SUMMARY OF BACKGROUND DATA: The importance of physical and psychosocial workloads as causal factors of low back pain has mostly been investigated in special occupational groups and with a cross-sectional design, which makes generalizability and interpretations more difficult. METHODS: The study comprised 2118 working men and women 20 to 59 years old (695 cases, and 1423 referents). Cases were defined as persons seeking care by any caregiver for low back pain. The exposure assessments were made through questionnaires and interviews about current and past physical and psychosocial loads during work and leisure time. RESULTS: In a logistic regression analysis, physical load from forward bending in men (RR = 1.8) and high physical load, in general, in women (RR = 2.0) showed increased relative risks. Psychosocial factors alone seemed to be of less importance in women, but "poor job satisfaction" and "mostly routine work without possibilities of learning" increased the risk in men. Combined current and past exposures further increased the risks. A combination of high physical and psychosocial loads increased the risk substantially, but few were exposed to such loads. Adjustment for lifestyle and other loads outside work did not change the results. CONCLUSION: Current and past physical and psychosocial occupational factors, both separately and combined, seem to be gender-specific, and to have a moderate impact on care-seeking for low back pain in a general working population.

Physical work load in physical education teachers.

The main objective was to measure and quantify exposure to physical work load in physical education teachers. A further aim was to establish the reproducibility of a three-week test-retest interval of self-reported physical load and to evaluate the agreement between registered and self-rated physical load. Thirty teachers, both female and male, volunteered to participate in the study. The physical load on the lower extremities, as well as the back and the cardio-vascular strain was recorded during one working day. The results indicate that the physical work load in this occupational group is considerable due to the load on the lower extremities. The demands of the cardio-vascular system are also relatively high in comparison to other occupational groups. The teachers could assess their activity quite well regarding heavy lifting and time spent sitting.

Collaboration between developing and developed countries and between developing countries in occupational health research and surveillance.

Collaborative occupational health and safety studies between counterparts in developing and developed countries and between developing countries have demonstrated their potential for improving occupational health and safety. Such collaboration in occupational health and safety is encouraged in the development of infrastructure in research empowerment and capacity building. This action includes the setting of priorities, the identification and documentation of problems, sponsorship, data bases and surveillance systems, technical support, methodology, publishing, research and training programs, controlled intervention, information exchange, and networking. Examples of priorities in occupational health and safety in the developing world include the informal sector (informally hired and independent workers), temporary work, pesticides, accidents, dusts, carcinogens, solvents, ergonomics, women and child labor, human immunodeficiency virus/acquired immunodeficiencey syndrome (HIV/AIDS), and transfer of hazardous materials and technologies. The sustainability of occupational health and safety structures and functions in the developing countries is a primary concern. Socioethical principles emphasize local, national, mutual and global gains. Examples of collaboration are given. Pervasive problems and strategies toward their solution are highlighted.

Higher relative, but lower absolute risks of myocardial infarction in women than in men: analysis of some major risk factors in the SHEEP study. The SHEEP Study Group.

OBJECTIVES: Middle-aged men have often been the subjects of multifactorial studies of myocardial infarction (MI) risk factors. One major objective of the SHEEP study was to compare the effects of different MI risk factors in women and men. DESIGN: SHEEP (Stockholm Heart Epidemiology Program) is a population-based case-referent study of causes of MI (first event) in Swedish women and men aged 45-70 years. During the period 1992-94, 2246 cases of MI were identified; 34% of the cases were women and 27% of the cases were fatal. One referent per case was chosen randomly from the Stockholm County population after stratification for the case's sex and age. Logistic regression was used to estimate the relative risks associated with risk factors of primary interest (diabetes, hypercholesterolaemia, hypertriglyceridaemia, hypertension, overweight, physical inactivity, smoking and job strain). RESULTS: The relative risk estimates ranged from 1.5 to 4.4 in women and from 1.3 to 2.9 in men (results for nonfatal cases and their referents). None of the 95% confidence intervals included 1.0. The relative risks were higher in the women than in the men (101-180%). The absolute risks, however, were all lower in the women than in the men. Estimates of Rothman's synergy index for gender ranged from 1.0 (hypertension) to 1.8 (current smoking). CONCLUSIONS: The indications of some effect modification due to sex (stronger risks in men for certain exposures) invoke the question of possible mechanisms.

Geographical differences of cancer incidence in Costa Rica in relation to environmental and occupational pesticide exposure.

BACKGROUND: This study describes geographical differences in cancer incidence in Costa Rica, and investigates if some of these differences may be related to pesticides. METHODS: Data were combined from the cancer registry (1981-1993), the 1984 population census, the 1984 agricultural census, and a national pesticide data set. The 81 counties of Costa Rica were the units for the ecological analyses. Adjacent counties were grouped into 14 regions (3 urban and 11 rural) with relatively similar socioeconomic characteristics. County indices for population density and agricultural variables were constructed and categorized. Differences across regions and categories were assessed by comparing observed numbers of incident cases to expected values derived from national rates. Within the tertile of most rural counties, rate ratios between categories of high and low pesticide use were calculated. RESULTS: In urban regions, excesses were observed for lung, colorectal, breast, uterus, ovary, prostate, testis, kidney, and bladder cancers; and in rural regions for gastric, cervical, penile, and skin cancers. Skin cancers (lip, melanoma, non-melanocytic skin and penile cancer) occurred in excess in coffee growing areas with extensive use of paraquat and lead arsenate. In the most rural subset, heavy pesticide use was associated with an increase of cancer incidence overall and at a considerable number of specific sites, including lung cancer (relative risk [RR] 2.0 for men and 2.6 for women) and all female hormone-related cancers (RR between 1.3 and 1.8). CONCLUSIONS: Regions and populations at high risk for specific cancers were identified. Several hypotheses for associations between pesticides and cancer emerged. The findings call for studies at the individual level.

Osteoarthrosis of the knee in men and women in association with overweight, smoking, and hormone therapy.

OBJECTIVES: The aim was to examine the relation between osteoarthrosis of the knee leading to prosthetic surgery among men and women and overweight, smoking, and hormone therapy. METHODS: A case-referent study was performed with a study base of all men and women, born 1921-1938, living in 14 counties in Sweden during 1991-95. The cases (n = 625) were identified through the Swedish Knee Arthroplasty Register. The referents (n = 548) were randomly selected through the central population register from the same counties. Detailed information on general health status, height, weight, smoking habits, medication, use of hormones, specific physical loads from occupation and housework, and sports activities was collected by a telephone interview and a postal questionnaire. The cases were classified in terms of high, medium or low/non-exposure to the factors studied, according to the distribution of variables among the referents. RESULTS: Women with high body mass index (BMI) at the age of 40 had a relative risk of 9.2 (95% CI 5.3, 16.0) of developing severe knee osteoarthrosis later in life, and for men at the same age the relative risk was 3.9 (95% CI 2.3, 6.4). Smokers were less likely to develop severe knee osteoarthrosis compared with nonsmokers. Oestrogen therapy for women over 50 showed an increased relative risk of 1.8 (95% CI 1.2, 2.6), while use of oral contraceptives did not influence the risk. CONCLUSION: Overweight is a risk factor for knee osteoarthrosis leading to prosthetic surgery in men and women, with the strongest relation for women. Oestrogen therapy after 50 increased the relative risk, while smoking decreased it.

Decision latitude, job strain, and myocardial infarction: a study of working men in Stockholm. The SHEEP Study Group. Stockholm Heart epidemiology Program.

OBJECTIVES: This study examined the role of decision latitude and job strain in the etiology of a first myocardial infarction. METHODS: Eligible case patients were all full-time working men 45 to 64 years of age who suffered a first myocardial infarction during the period January 1992 to January 1993 in the greater Stockholm region. Referents were selected from the general population. Participation rates were 82% (case patients) and 75% (referents). RESULTS: Both inferred and self-reported low decision latitude were associated with increased risk of a first myocardial infarction, although this association was weakened after adjustment for social class. A decrease in inferred decision latitude during the 10 years preceding the myocardial infarction was associated with increased risk after all adjustments, including chest pain and social class. The combination of high self-reported demands and low self-reported decision latitude was an independent predictor of risk after all adjustments. CONCLUSIONS: Both negative change in inferred decision latitude and self-reported job strain are important risk indicators in men less than 55 years of age and in blue-collar workers.

Mortality and cancer incidence in Swedish battery workers exposed to cadmium and nickel.

OBJECTIVE: To follow up cancer incidence and mortality in a group of Swedish battery workers exposed to nickel hydroxide and cadmium oxide. METHODS: 869 workers, employed at least one year between the years 1940 and 1980 were followed up until 1992. Vital status and causes of death were obtained from the Swedish cause of death registry. Cancer morbidity was retrieved from the Swedish cancer registry. Regional reference rates were used to compute the expected numbers of deaths and cancers. RESULTS: Up to 31 December, 1992, a total of 315 deaths (292 in men and 23 in women) had occurred in the cohort. For men, the overall standardised mortality ratio (SMR) was 106 (95% confidence interval (95% CI) 93.7 to 118) and for women 83.8 (95% CI 53.1 to 126). The SMRs for total cancer mortality were 125 (95% CI 98.2 to 157) for men and 69.5 (95% CI 25.5 to 151) for women. The SMR for lung cancer in men was 176 (95% CI 101 to 287). No lung cancers were found among female workers. Up to 31 December, 1991, a total of 118 cancers had occurred in the cohort. A significantly increased standardised incidence ratio (SIR) was found for cancer of the nose and nasal sinuses in men, three cases v 0.36 expected, yielding an SIR of 832 (95% CI 172 to 2430). Applying a 10 year latency period in cohort members exposed to > or = 1000 micrograms cadmium/m3, the SIR was 1107 (95% CI 134 to 4000). Similarly, for cohort members exposed to 2000 micrograms nickel/m3, the SIR was 1080 (95% CI 131 to 3900). CONCLUSION: There was an increased overall risk for lung cancer, but no exposure-response relation between cumulative exposure to cadmium or nickel and risk of lung cancer. There was a highly significant increased risk of cancer of the nose and nasal sinuses, which may be caused by exposure to nickel or cadmium or a combination of both exposures.

Unintentional fatal paraquat poisonings among agricultural workers in Costa Rica: report of 15 cases.

This study analyzes the exposure circumstances of 15 fatal occupational paraquat poisonings. To evaluate the potential danger of dermal absorption and the amount needed to produce a fatal outcome in the event of oral intake, we reviewed the medical records and autopsy protocols and interviewed relatives. Five fatalities were due to ingestion of a mouthful of paraquat concentrate, and five to intake of a smaller amount; three cases were associated with dermal exposure, and in two, there was no evidence of either oral or dermal exposure. Several cases concerned diluted paraquat spray. The clinical and pathomorphological findings, including a "blinded" evaluation of lung slides, were consistent with paraquat poisoning in all cases. Difficulties in establishing the diagnosis and recognizing the exposure were identified, as well as classification of unintentional poisonings as suicides at autopsy. The findings suggest that paraquat may cause fatal poisonings by ingestion of small amounts, by dermal absorption of diluted paraquat, and possibly by inhalation. More conclusive studies are warranted.

A cohort study of Swedish capacitor manufacturing workers exposed to polychlorinated biphenyls (PCBs).

Mortality and cancer incidence were investigated among 242 male capacitor manufacturing workers, exposed to polychlorinated biphenyls (PCBs) for at least six months between 1965 and 1978. Mortality and cancer incidence were followed from 1965 to 1991. There was a significantly increased mortality from cardiovascular diseases among those employed for at least five years in high-exposed jobs, with a latency of 20 years. There were two cases of cancer of the liver and bile ducts, which previously has been associated with PCB exposure, both in epidemiological and animal experimental studies. No data on smoking habits were available. The study supports some previous findings of an increased risk of cancer of the liver and bile ducts after exposure to PCBs. The reason for the excess of cardiovascular deaths in the high-exposure group is not known and deserves evaluation in future studies.

Evaluation of the Q16 questionnaire on neurotoxic symptoms and a review of its use.

OBJECTIVES: The questionnaire 16 (Q16) is commonly used to study prevalences of neurotoxic symptoms among workers exposed to organic solvents. It has also been recommended that exposed workers reporting more than six symptoms should be referred for further examination of possible chronic toxic encephalopathy. It would be useful to know whether symptoms reported in the questionnaire also reflect impairment of similar functions measured with objective or semiobjective methods in a formerly highly exposed group. METHODS: 135 painters and 71 carpenters answered the Q16, were interviewed about symptoms compatible with an organic brain damage, and took a battery of psychometric tests. A subsample of 52 painters and 45 carpenters were interviewed for psychiatric diagnosis according to Diagnostic and Statistical Manual for Mental Disorders, 3rd version (DSM III) and their vibration thresholds in hands and feet were measured. The entire group was followed up in the register of diagnoses at early retirement 1971-93. The lifetime exposure to organic solvents was assessed. Current exposure to organic solvents was found to be low or none. RESULTS: The prevalence of people with more than six symptoms in the Q16 rose with increasing cumulative exposure to solvents. The sensitivity of the questionnaire (more than six symptoms) to detect people who were assessed to exhibit symptoms compatible with an organic brain damage was only 38%. One of seven people who had retired early with a diagnosis compatible with a chronic toxic encephalopathy, and two of five people with a psychiatric diagnosis compatible with this condition, had more than six symptoms in the Q16. The agreement between Q16 replies and psychometric test results, as well as other examinations, was low. CONCLUSIONS: The notable exposure-response relation indicates that the questionnaire is useful for comparison of groups with different exposures to organic solvents. There was low agreement between the number of symptoms on the questionnaire and the assessment of symptoms compatible with organic brain damage, as well as psychiatric, or early retirement diagnoses compatible with chronic toxic encephalopathy. The questionnaire does not seem useful for screening of patients with chronic toxic encephalopathy in groups without ongoing exposure to organic solvents.