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1.
Environ Res ; 150: 600-605, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-26922260

RESUMO

PURPOSE: Knowledge about changes in exposure to toxic metals over time remains very sparse, in particular for children, the most vulnerable group. Here, we assessed whether a reduction in environmental pollution with cadmium (Cd) and mercury (Hg) caused a change in exposure over time. In total, 1257 children (age 4-9) in two towns in Sweden were sampled once in 1986-2013. Blood concentrations of Cd (b-Cd; n=1120) and Hg (b-Hg; n=560) were determined. RESULTS: The median b-Cd was 0.10 (geometric mean 0.10; range 0.010-0.61) µg/L and b-Hg was 0.91 (geometric mean 0.83; range 0.021-8.2) µg/L. Children living close to a smelter had higher b-Cd and b-Hg than those in urban and rural areas. There was no sex difference in b-Cd or b-Hg, and b-Cd and b-Hg showed no significant accumulation by age. b-Cd decreased only slightly (0.7% per year, p<0.001) over the study period. In contrast, b-Hg did show a clear decrease over the study period (3% per year, p<0.001). CONCLUSIONS: The exposure to Cd was very low but still might increase the risk of disease later in life. Moreover, b-Cd only showed a minor decrease, indicating that Cd pollution should be further restricted. b-Hg was relatively low and decreasing, probably because of reduced use of dental amalgam and lower Hg intake from fish. The b-Cd and b-Hg levels decreased much less than the levels of lead in the blood as previously found in the same children.


Assuntos
Cádmio/sangue , Poluentes Ambientais/sangue , Mercúrio/sangue , Criança , Pré-Escolar , Monitoramento Ambiental/estatística & dados numéricos , Feminino , Humanos , Masculino , Suécia
2.
Int Arch Occup Environ Health ; 85(3): 311-6, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21701834

RESUMO

OBJECTIVE: Blood lead (B-Pb), one of the most used toxicological biomarker all kind, has serious limitations. Thus, the objective is to evaluate whether plasma lead (P-Pb) is more adequate. METHODS: A long-term follow-up study of five cases of lead poisoning. P-Pb was analysed by inductively coupled plasma mass spectrometry. Kinetics after end of exposure was modelled. RESULTS: P-Pb at severe poisoning was about 20 µg/L; haematological effects at about 5 µg/L. Biological half-time of P-Pb was about 1 month; B-Pb decay was much slower. CONCLUSION: P-Pb is a valuable biomarker of exposure to and risk, particularly at high exposure.


Assuntos
Intoxicação por Chumbo/sangue , Chumbo/farmacocinética , Anemia/induzido quimicamente , Anemia/patologia , Biomarcadores/sangue , Feminino , Meia-Vida , Hemoglobinas/análise , Humanos , Chumbo/metabolismo , Chumbo/toxicidade , Intoxicação por Chumbo/patologia , Masculino , Espectrometria de Massas/métodos , Pessoa de Meia-Idade , Plasma , Sintase do Porfobilinogênio/genética , Adulto Jovem
3.
Environ Res ; 109(8): 991-6, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19733845

RESUMO

Environmental contaminants such as cadmium and persistent organochlorine pollutants have been proposed as risk factors of osteoporosis, and women may be at an increased risk. To assess associations between exposure to cadmium and two different POPs (2,2',4,4',5,5'-hexachlorobiphenyl CB-153, 1,1-dichloro-2,2-bis(p-chlorophenyl)-ethylene p,p'-DDE), on one hand, and bone effects, on the other, in a population-based study among postmenopausal (60-70 years) Swedish women with biobanked blood samples. The study included 908 women and was designed to have a large contrast of bone mineral densities, measured with a single photon absorptiometry technique in the non-dominant forearm. Biochemical markers related to bone metabolism were analyzed in serum. Exposure assessment was based on cadmium concentrations in erythrocytes and serum concentrations of CB-153 and p,p'-DDE. Cadmium was negatively associated with bone mineral density and parathyroid hormone, positively with the marker of bone resorption. However, this association disappeared after adjustment for smoking. The major DDT metabolite (p,p'-DDE) was positively associated with bone mineral density, an association which remained after adjustment for confounders, but the effect was weak. There was no evidence that the estrogenic congener (CB-153) was associated with any of the bone markers. In conclusion, no convincing associations were observed between cadmium and POPs, on one hand, and bone metabolism markers and BMD, on the other.


Assuntos
Densidade Óssea/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Cádmio/toxicidade , Exposição Ambiental , Poluentes Ambientais/toxicidade , Hidrocarbonetos Clorados/toxicidade , Pós-Menopausa , Idoso , Osso e Ossos/metabolismo , Feminino , Humanos , Pessoa de Meia-Idade
4.
J Electromyogr Kinesiol ; 16(2): 125-36, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16102977

RESUMO

For measuring the physical exposure/workload in studies of work-related musculoskeletal disorders, direct measurements are valuable. However, the between-days and between-subjects variability, as well as the precision of the method per se, are not well known. In a laboratory, six women performed three standardised assembly tasks, all of them repeated on three different days. Triaxial inclinometers were applied to the head, upper back and upper arms. Between-days (within subjects) and between-subjects (within tasks) variance components were derived for the 10th, 50th and 90th percentiles of the angular and the angular velocity distributions, and for the proportion of time spent in predefined angular sectors. For percentiles of the angular distributions, the average between-days variability was 3.4 degrees , and the between-subjects variability 4.0 degrees . For proportion of time spent in angular sectors, the variability depended on the percentage of time spent in the sector; the relative variability was scattered and large, on average 103% between days and 56% between subjects. For the angular velocity percentiles, the average between-days variability was 7.9%, and the average between-subjects variability was 22%. The contribution of the measurement procedure per se to the between-days variability, i.e., the imprecision of the method, was small: less than 2 degrees for angles and 3% for angular velocity.


Assuntos
Movimento/fisiologia , Pescoço/fisiologia , Postura/fisiologia , Extremidade Superior/fisiologia , Carga de Trabalho , Aceleração , Adulto , Fenômenos Biomecânicos , Feminino , Humanos , Pessoa de Meia-Idade
5.
Environ Health Perspect ; 25: 57-65, 1978 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-363410

RESUMO

The available data on the influence of selenium on the toxicity of methylmercury and of methylmercury on selenium as a nutrient and toxic agent are reviewed. Selenium as selenite has a relative protective effect on acute and subacute toxicity of methylmercury in the rat and the quail. The protective mechanism is far from clear. Of special interest is the fact that selenium-treated animals may remain unaffected, even when they have attained tissue mercury levels otherwise associated with toxic effects. Selenite causes some increase of tissue mercury levels in methylmercury-exposed animals. On the other hand, methylmercury induces a remarkable enhancement of organ concentrations of selenium in animals given selenite. The interaction between selenium and methylmercury is in many ways different from that between selenium and inorganic mercury, and also from that between selenium and other metals. Due to the considerable interspecies differences in the toxicity of methylmercury, the available data do not allow conclusions on interactions in man. Practical implications of a possible protective effect of selenium on methylmercury toxicity in humans are discussed.


Assuntos
Compostos de Metilmercúrio/antagonistas & inibidores , Selênio/farmacologia , Animais , Biotransformação , Interações Medicamentosas , Enzimas/metabolismo , Absorção Intestinal/efeitos dos fármacos , Compostos de Metilmercúrio/metabolismo , Compostos de Metilmercúrio/toxicidade , Placenta/metabolismo , Ligação Proteica/efeitos dos fármacos , Frações Subcelulares/metabolismo
6.
Environ Health Perspect ; 105(5): 522-6, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9222138

RESUMO

We investigated blood lead (B-Pb) and mercury (B-Hg) levels and auditory sensory-neural function in 62 Andean school children living in a Pb-contaminated area of Ecuador and 14 children in a neighboring gold mining area with no known Pb exposure. The median B-Pb level for 62 children in the Pb-exposed group was 52.6 micrograms/dl (range 9.9-110.0 micrograms/dl) compared with 6.4 micrograms/dl (range 3.9-12.0 micrograms/dl) for the children in the non-Pb exposed group; the differences were statistically significant (p < 0.001). Auditory thresholds for the Pb-exposed group were normal at the pure tone frequencies of 0.25-8 kHz over the entire range of B-Pb levels, Auditory brain stem response tests in seven children with high B-Pb levels showed normal absolute peak and interpeak latencies. The median B-Hg levels were 0.16 micrograms/dl (range 0.04-0.58 micrograms/dl) for children in the Pb-exposed group and 0.22 micrograms/dl (range 0.1-0.44 micrograms/dl) for children in the non-Pb exposed gold mining area, and showed no significant relationship to auditory function.


Assuntos
Exposição Ambiental/efeitos adversos , Perda Auditiva Neurossensorial/induzido quimicamente , Intoxicação por Chumbo/complicações , Adolescente , Audiometria de Tons Puros , Limiar Auditivo , Estudos de Casos e Controles , Cerâmica , Criança , Pré-Escolar , Equador , Potenciais Evocados Auditivos do Tronco Encefálico , Feminino , Perda Auditiva Neurossensorial/diagnóstico , Humanos , Intoxicação por Chumbo/sangue , Masculino
7.
J Clin Epidemiol ; 53(7): 715-21, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10941949

RESUMO

To validate a detailed questionnaire for assessment of environmental tobacco smoke (ETS) exposure by the biomarker cotinine in various media, a population-based study in the urban area of Malmö, Sweden was performed in children aged 8-13 years with and without asthmatic symptoms. There were strong correlations between urinary and saliva cotinine concentrations and also, though to a lesser extent, between these media and plasma. Even a detailed questionnaire gave only a rough picture of the ETS exposure, as indicated by the biomarkers. In a multivariate model, the most significant questionnaire-derived predictor of the cotinine levels was the maternal smoking habits; other questionnaire variables gave only a minimal explained variance. Children with a history of asthmatic symptoms had statistically significantly lower median cotinine levels in urine and saliva compared to referent children, most likely because of the antismoking information to their parents. This should be considered in epidemiological studies of ETS risks.


Assuntos
Asma/epidemiologia , Asma/metabolismo , Cotinina/análise , Poluição por Fumaça de Tabaco , Adolescente , Asma/etiologia , Criança , Cotinina/sangue , Cotinina/urina , Escolaridade , Feminino , Humanos , Masculino , Análise de Regressão , Fatores de Risco , Saliva/química , Inquéritos e Questionários
8.
Chest ; 91(6): 865-9, 1987 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3646942

RESUMO

We measured lung density by means of x-ray computed tomography and lung mechanics in 33 workers exposed to asbestos cement and in 39 normal subjects. The exposed group showed evidence of lung fibrosis with reduced static lung volumes and lung compliance, although only three subjects had signs of interstitial fibrosis at standard chest radiography. Lung density was significantly increased in the exposed workers compared to control subjects, with greater differences between nonsmokers than between smokers. Lung density correlated inversely with static lung volumes. There was no appreciable difference in the regional distribution of lung density between exposed workers and control subjects. We conclude that lung density is often increased in workers with mild asbestosis, even in the presence of a normal chest radiograph. Measurement of lung density may be of value in the evaluation of asbestos-exposed workers for assessment of the extent of parenchymal disease.


Assuntos
Asbestose/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Hidróxido de Cálcio , Materiais de Construção , Humanos , Pulmão/fisiopatologia , Complacência Pulmonar , Medidas de Volume Pulmonar , Masculino , Pessoa de Meia-Idade , Fumar , Trabalho Respiratório
9.
Int J Epidemiol ; 26(3): 610-9, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9222787

RESUMO

BACKGROUND: The high and increasing prevalence of childhood asthma is a major public health issue. Various risk factors have been proposed in local studies with different designs. METHODS: We have made a questionnaire study of the prevalence of childhood asthma, potential risk factors and their relations in four regions in Scandinavia (Umeå and Malmö in Sweden, Kuopio in eastern Finland and Oslo, Norway). One urban and one less urbanized area were selected in each region, and a study group of 15962 children aged 6-12 years was recruited. RESULTS: The prevalence of symptoms suggestive of asthma varied considerably between different areas (dry cough 8-19%, asthma attacks 4-8%, physician-diagnosed asthma 4-9%), as did the potential risk factors. Urban residency was generally not a risk factor. However, dry cough was common in the most traffic polluted area. Exposure to some of the risk factors. such as smoking indoors and moisture stains or moulds at home during the first 2 years of life, resulted in an increased risk. However, current exposure was associated with odds ratios less than one. CONCLUSIONS: Our findings were probably due to a combination of early impact and later avoidance of these risk factors. The effects of some risk factors were found to differ significantly between regions. No overall pattern between air pollution and asthma was seen, but air pollution differed less than expected between the areas.


Assuntos
Poluição do Ar/estatística & dados numéricos , Asma/epidemiologia , Exposição Ambiental/estatística & dados numéricos , Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Criança , Intervalos de Confiança , Tosse/epidemiologia , Estudos Transversais , Saúde da Família , Feminino , Humanos , Modelos Logísticos , Masculino , Razão de Chances , Prevalência , Características de Residência/estatística & dados numéricos , Estudos Retrospectivos , Fatores de Risco , Países Escandinavos e Nórdicos/epidemiologia , Fatores Sexuais , Inquéritos e Questionários , Saúde da População Urbana/estatística & dados numéricos
10.
Toxicol Sci ; 46(2): 247-53, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10048127

RESUMO

In 42 lead-exposed workers (22 male and 20 female), we found a close nonlinear relation between blood and plasma lead concentrations, determined by inductively coupled plasma mass spectrometry (ICP-MS). The concentration medians and ranges were lead in whole blood, 270 (97 to 950) micrograms/L and lead in plasma, 1.1 (0.2 to 13) micrograms/L. Proteins from lysed erythrocytes were studied by gel chromatography with ICP-MS detection. We then found capacity-limited binding for lead to delta-aminolevulinic acid dehydratase (ALAD), as well as to two other components (with apparent molecular masses of 45 and < 10 kDa, respectively). The strongest affinity for lead was indicated for ALAD (35-81% of the lead in blood) and could be described by a capacity of 850 micrograms/L and a dissociation constant of 1.5 micrograms/L. The 45-kDa protein carried 12-26% of the blood lead, and the < 10-kDa component less than 1%. A model based on these three components, plus a fourth one for unrecovered lead (2-45%), is proposed. No binding of lead to hemoglobin was found. There was an association between zinc and lead in whole blood; however, zinc did not significantly affect the lead distribution in erythrocytes.


Assuntos
Hemoglobinas/metabolismo , Chumbo/sangue , Exposição Ocupacional/efeitos adversos , Sintase do Porfobilinogênio/metabolismo , Zinco/metabolismo , Cromatografia em Gel , Interações Medicamentosas , Feminino , Humanos , Masculino , Espectrometria de Massas , Modelos Biológicos , Ligação Proteica
11.
Recent Results Cancer Res ; 154: 177-84, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-10026999

RESUMO

It has not previously been clear whether cytogenetic biomarkers in healthy subjects will predict cancer. Earlier analyses of a Nordic and an Italian cohort indicated predictivity for chromosomal aberrations (CAS) but not for sister chromatid exchanges (SCES). A pooled analysis of the updated cohorts, forming a joint study base of 5271 subjects, will now be performed, allowing a more solid evaluation. The importance of potential effect modifiers, such as gender, age at testing, and time since testing, will be evaluated using Poisson regression models. Two other potential effect modifiers, occupational exposures and smoking, will be assessed in a case-referent study within the study base.


Assuntos
Aberrações Cromossômicas , Inquéritos Epidemiológicos , Micronúcleos com Defeito Cromossômico , Neoplasias/etiologia , Saúde Ocupacional , Troca de Cromátide Irmã , Biomarcadores , Humanos , Incidência , Neoplasias/epidemiologia , Neoplasias/genética
12.
Toxicology ; 103(2): 127-36, 1995 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-8545845

RESUMO

Relationships between chemical structure and immunogenicity have been studied in 13 dicarboxylic acid anhydrides. Guinea-pigs were immunized intradermally by a single dose of 0.3 M solutions of succinic anhydride (SA), maleic anhydride (MA), methylmaleic anhydride (MMA), cis-cyclohexane-1,2-dicarboxylic anhydride (cis-HHPA), trans-cyclohexane-1,2-dicarboxylic anhydride (trans-HHPA), 4-methylcyclohexane-1,2-dicarboxylic anhydride (MHHPA), cis-1,2,3,6-tetrahydrophthalic anhydride (THPA1236), cis-3,4,5,6-tetrahydrophthalic anhydride (THPA3456), cis-3-methylcyclohex-4-ene-1,2-dicarboxylic anhydride (MTHPA34), cis-4-methylcyclohex-4-ene-1,2-dicarboxylic anhydride (MTHPA44), phthalic anhydride (PA), 4-methylphthalic anhydride (MPA), and trimellitic anhydride (TMA) in olive oil. Specific IgE, IgG, IgG1, and IgG2 antibodies against guinea-pig serum albumin conjugates of the anhydrides were determined by passive cutaneous anaphylaxis (PCA) tests and enzyme-linked immunoabsorbant assay (ELISA). Specific IgG was significantly increased in all animals, except those immunized with THPA3456 and SA, which sensitized only 3/9 and 7/9 animals, respectively. Furthermore, the specific IgG values were very low in the SA group. The titers of specific IgG1 and IgG2 were increased in the IgG-positive animals. Specific IgE was positive in all animals immunized with MA, MHHPA, MTHPA (both isomers), and MPA, and in 6/9 and 5/9 guinea pigs immunized with TMA and MMA, respectively. The IgE titers were generally very low; PCA was negative after dilutions to 1:32, or less. The results indicate a considerable variation in the sensitizing potential between different organic acid anhydrides. The most marked general effect of the chemical structure on immunogenicity was the enhancement of antibody formation when a hydrogen atom in the anhydride was substituted with a methyl group.


Assuntos
Anidridos/imunologia , Antígenos/imunologia , Imunoglobulina E/biossíntese , Imunoglobulina G/biossíntese , Anidridos/administração & dosagem , Anidridos/química , Animais , Especificidade de Anticorpos , Reações Antígeno-Anticorpo/efeitos dos fármacos , Antígenos/administração & dosagem , Antígenos/química , Ensaio de Imunoadsorção Enzimática , Cobaias , Haptenos/metabolismo , Imunização , Injeções Intradérmicas , Masculino , Anafilaxia Cutânea Passiva , Relação Estrutura-Atividade
13.
Toxicology ; 118(2-3): 223-32, 1997 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-9129176

RESUMO

The objective of the study was to evaluate the structure-activity relationship for the antigenic activity of different organic acid anhydrides (OAAs). The specificity of guinea pig (GP) IgG1 to different anhydrides was studied by ELISA-inhibition, PCA, and airway provocation tests of cross-reactivity with different OAA conjugates. In the airway provocation tests, lung resistance and plasma extravasation of Evan's Blue dye was measured. The ELISA-inhibition tests showed a wide range in antibody specificity. Modelling of ring configuration, methyl group substitution, double bond position, and cis/trans isomerism of anhydride forming carboxyl groups influenced the specificity. There was a general consistency in cross-reactivity of anti-cis-hexahydrophthalic anhydride IgG1 versus GP serum albumin conjugates of trans-hexahydrophthalic anhydride, phthalic anhydride, and succinic anhydride as shown by ELISA-inhibition, PCA, and airway provocation tests. It is concluded that various modifications of the chemical structures of a hapten are recognized by the hapten-specific antibodies, and that these differences may have clinical relevance. In particular, the ring structure and the positions of double bonds and of methyl groups are important. Further, the in-vitro ELISA-inhibition tests show a good agreement with the in-vivo PCA and bronchial provocation tests.


Assuntos
Anidridos/imunologia , Especificidade de Anticorpos/efeitos dos fármacos , Resistência das Vias Respiratórias/efeitos dos fármacos , Anidridos/química , Anidridos/toxicidade , Animais , Especificidade de Anticorpos/imunologia , Reações Antígeno-Anticorpo , Testes de Provocação Brônquica , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática , Extravasamento de Materiais Terapêuticos e Diagnósticos , Cobaias , Imunização , Imunoglobulina G/metabolismo , Técnicas In Vitro , Anafilaxia Cutânea Passiva , Estereoisomerismo , Relação Estrutura-Atividade
14.
Eur J Clin Nutr ; 47(2): 132-40, 1993 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8436091

RESUMO

Fatty acid composition of serum phosphatidylcholine was studied in subjects living in the same area and selected for high consumption of fat fish, high consumption of lean fish, moderate or no consumption of fish. The proportion of eicosapentaenoic acid (20:5) in serum phosphatidylcholine was fourfold higher, and that of docosahexaenoic acid (22:6) twofold higher among high consumers of fish compared to non-consumers, and these proportions were also higher in fat fish consumers than in high consumers of lean fish, and in moderate consumers compared to non-consumers. In the whole group the intake of fat fish was correlated to the proportions of 20:5, 22:6 and total n-3 fatty acids in serum phosphatidylcholine. The estimated intake of total n-3 fatty acids from fish was highly correlated to the proportions of these fatty acids in serum phosphatidylcholine (r = 0.87). Plasma triglyceride concentration was lower among high fat fish consumers than in other groups, but no differences between groups were observed for concentration of cholesterol, LDL cholesterol, and HDL cholesterol. It is concluded that subjects who consume high amounts of fat fish in their normal diet attain approximately the same proportions of n-3 fatty acids in serum phosphatidylcholine as reported for subjects taking fish oil supplements, and that fatty acid composition of serum lipids can be used as a marker of intake of fat fish.


Assuntos
Dieta/normas , Ácidos Docosa-Hexaenoicos/química , Ácido Eicosapentaenoico/química , Peixes , Fosfatidilcolinas/sangue , Adulto , Animais , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Peixes/classificação , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação Nutricional , Inquéritos Nutricionais , Fosfatidilcolinas/química , Suécia , Triglicerídeos/sangue
15.
Phys Med Biol ; 34(12): 1833-45, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2616639

RESUMO

In vivo bone lead measurements have been made on a group of about 120 people, most of whom were lead exposed workers. Two different x-ray fluorescence (XRF) techniques were used to make measurements at three bone sites. Finger lead was measured using 57Co sources, and lead measurements were made in both tibia and calcaneus with a technique based on 109Cd sources. The results of the bone lead measurements correlated strongly with each other and with the index of cumulative exposure, thus confirming the value and reliability of these in vivo measurements as a tool in the study of chronic lead exposure. Measurement precision, +/- 1 standard deviation, was highest for tibia +/- 7.4 micrograms (g bone mineral)-1, +/- 16.6 micrograms (g bone mineral)-1 for the calcaneus and lowest for phalangeal lead +/- 25.0 micrograms (g bone mineral)-1. Maximum absorbed doses to the skin were comparable for all three measurements (1-3 mGy). The mean whole body dose equivalents were all low, but that for the finger measurement, 0.1 microSv, was significantly less than for the calcaneus and tibia measurements 3-5 microSv.


Assuntos
Osso e Ossos/análise , Chumbo/análise , Espectrometria por Raios X/métodos , Calcâneo/análise , Exposição Ambiental , Dedos , Humanos , Masculino , Tíbia/análise
16.
Toxicol Lett ; 64-65 Spec No: 17-24, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1471171

RESUMO

Knowledge of the body burden of a metal is important for evaluation of exposure and risk. Traditionally, the burden has been estimated through levels in blood, urine, hair, or shed teeth, or by mobilization tests. However, all these methods have limitations. In vivo methods for determination of cadmium in kidney by neutron activation analysis or X-ray fluorescence (XRF) reflect the burden, long-term exposure, and risk of toxic effect. In vivo determination by XRF of lead in fingerbone, tibia, or calcaneus reflect the long-term exposure, and should become a valuable tool in epidemiological studies, especially of chronic effects.


Assuntos
Cádmio/análise , Chumbo/análise , Exposição Ocupacional , Carga Corporal (Radioterapia) , Osso e Ossos/química , Humanos
17.
Mutat Res ; 261(3): 217-23, 1991 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1719414

RESUMO

Comparing 21 rotogravure printers exposed to toluene (medians: time-weighted air level 150 mg/m3, blood toluene 1.6 mumole/l) and 21 unexposed controls (median blood toluene less than or equal to 0.01 mumole/l) there was a significant increase in the frequency of micronuclei (MN) in pokeweed mitogen (PWM)-stimulated peripheral blood lymphocytes in the printers, as compared to the controls (2.8% vs. 1.5%; p = 0.03; all p adjusted for age and smoking). The frequency of small MN (size ratio MN/main nucleus less than or equal to 0.03) in PWM-stimulated lymphocytes was associated with the exposure (1% vs. 0.3%; p = 0.05). Furthermore, among the exposed subjects there was an association between blood toluene and small MN (0.17% per mumole/l; p = 0.0005). Small MN in phytohemagglutinin (PHA) cultures displayed no association with any exposure parameter. However, in the printers, an estimated cumulative exposure index was weakly correlated with the frequency of total MN in PHA-stimulated cells (0.00003% per mg/m3 x year; p = 0.07). Among the printers, chromosomal breaks in PHA-stimulated cells were associated with the duration of earlier benzene exposure (0.03% per year; p = 0.01). The results of this study strongly indicate that toluene causes a clastogenic effect on the B-cells even at low exposure levels. Further, earlier benzene exposure seems to have caused chromosomal breaks in T-cells.


Assuntos
Benzeno/efeitos adversos , Aberrações Cromossômicas , Exposição Ocupacional , Impressão , Tolueno/efeitos adversos , Adulto , Linfócitos B/efeitos dos fármacos , Humanos , Ativação Linfocitária , Masculino , Micronúcleos com Defeito Cromossômico/patologia , Pessoa de Meia-Idade , Fito-Hemaglutininas , Mitógenos de Phytolacca americana , Linfócitos T/efeitos dos fármacos , Tolueno/sangue
18.
Mutat Res ; 405(2): 171-8, 1998 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-9748557

RESUMO

The cytogenetic endpoints in peripheral blood lymphocytes: chromosomal aberrations (CA), sister chromatid exchange (SCE) and micronuclei (MN) are established biomarkers of exposure for mutagens or carcinogens in the work environment. However, it is not clear whether these biomarkers also may serve as biomarkers for genotoxic effects which will result in an enhanced cancer risk. In order to assess this problem, Nordic and Italian cohorts were established, and preliminary results from these two studies indicated a predictive value of CA frequency for cancer risk, whereas no such associations were observed for SCE or MN. A collaborative study between the Nordic and Italian research groups, will enable a more thorough evaluation of the cancer predictivity of the cytogenetic endpoints. We here report on the establishment of a joint data base comprising 5271 subjects, examined 1965-1988 for at least one cytogenetic biomarker. Totally, 3540 subjects had been examined for CA, 2702 for SCE and 1496 for MN. These cohorts have been followed-up with respect to subsequent cancer mortality or cancer incidence, and the expected values have been calculated from rates derived from the general populations in each country. Stratified cohort analyses will be performed with respect to the levels of the cytogenetic biomarkers. The importance of potential effect modifiers such as gender, age at test, and time since test, will be evaluated using Poisson regression models. The remaining two potential effect modifiers, occupational exposures and smoking, will be assessed in a case-referent study within the study base.


Assuntos
Biomarcadores Tumorais , Neoplasias/epidemiologia , Saúde Ocupacional , Vigilância da População , Aberrações Cromossômicas , Estudos de Coortes , Bases de Dados Factuais , Europa (Continente)/epidemiologia , Feminino , Seguimentos , Humanos , Incidência , Masculino , Micronúcleos com Defeito Cromossômico , Neoplasias/diagnóstico , Neoplasias/genética , Valor Preditivo dos Testes , Fatores de Risco , Troca de Cromátide Irmã
19.
Scand J Work Environ Health ; 2(3): 176-84, 1976 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-788149

RESUMO

During 1 h two healthy volunteers, not earlier exposed occupationally to lead, inhaled about 100 mg of lead as a mixture of lead oxides and lead sulfate. Maximum blood lead (PbB) concentrations of about 0.5 mg/1 and minimum blood cell delta-aminolevulinic acid dehydratase activities (ALAD) (6% of the preexposure values) were observed within 38 h after exposure. PbB and ALAD returned to preexposure levels after about 300 and 150 days. A highly significant correlation between ALAD and PbB was seen even at lead levels in the range 0.1-0.2 mg/1. Delta-aminolevulinic acid, coproporphyrin and lead in the urine (ALAU, CPU, and PbU, respectively) increased. The peak levels occurred after about 15 h for ALAU and CPU and after about 24 h for PbU. There was a very good correlation between log PbU and lin PbB. ALAU increased already at PbB levels of about 0.3 mg/1.


Assuntos
Chumbo/metabolismo , Adulto , Ácido Aminolevulínico/metabolismo , Ácido Aminolevulínico/urina , Ensaios Clínicos como Assunto , Coproporfirinas/urina , Ambiente Controlado , Exposição Ambiental , Seguimentos , Humanos , Chumbo/sangue , Chumbo/urina , Masculino , Sintase do Porfobilinogênio/sangue
20.
Scand J Work Environ Health ; 1(1): 54-9, 1975 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1235859

RESUMO

The gamma-aminolevulinic acid dehydratase (ALA-D) activity in blood cells was studied in 15 subjects exposed to methylmercury through consumption of contaminated fish and 19 "unexposed" subjects with a similar sex and age distribution. The exposed subjects had a mean mercury level of 120 (range 15-370) ng/g blood cells while the controls had 9 (range 4-15) ng/g. Both groups had the same mean level of lead in whole blood (10+/-1 mug/100 ml). ALA-D activity decreased statistically significantly as both mercury and lead levels in the blood cells increased.


Assuntos
Eritrócitos/enzimologia , Hidroliases/sangue , Compostos de Metilmercúrio/efeitos adversos , Sintase do Porfobilinogênio/sangue , Adulto , Idoso , Eritrócitos/efeitos dos fármacos , Feminino , Produtos Pesqueiros/efeitos adversos , Contaminação de Alimentos , Humanos , Chumbo/sangue , Masculino , Mercúrio/sangue , Pessoa de Meia-Idade , Plasma/metabolismo
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