RESUMO
Epidemiological studies have reported that exposure to toxic metals like cadmium (Cd) may promote the development of musculoskeletal diseases, such as osteoporosis, rheumatoid arthritis (RA), and osteoarthritis (OA), among others. The objective of this review is to summarize the molecular mechanisms of inflammation and oxidative stress activated by Cd at the bone level, particularly in osteoporosis, RA, and OA. Cadmium can increase bone resorption, affect the activity of osteoclasts and calcium (Ca) absorption, and impair kidney function, which favors the development of osteoporosis. In the case of RA, Cd interferes with the activity of antioxidant proteins, like superoxide dismutase (SOD) and catalase (CAT). It also promotes an inflammatory state, inducing the process of citrullination, which affects the proteins of immune response. On the other hand, accumulation of Cd in the tissues and blood of smokers has been related to the development of some musculoskeletal diseases. Therefore, knowing the negative impact of Cd toxicity at the articular level can help understand the damage mechanisms it produces, leading to the development of such diseases.
Assuntos
Cádmio/toxicidade , Poluentes Ambientais/toxicidade , Doenças Musculoesqueléticas/induzido quimicamente , Animais , Cádmio/normas , Exposição Ambiental/normas , Poluentes Ambientais/normas , HumanosRESUMO
Human activities are associated with emissions of various metals into the environment, among which the heavy metals lead and cadmium stand out, as they pose a risk to human life even at low concentrations. Thus, accurate knowledge of the levels of these metals exhibited by the overall population, including children, is important. The aim of this study was to estimate the concentrations of lead and cadmium in the blood of adults, adolescents and children residing in the city of São Paulo, assess factors associated with higher lead and cadmium blood levels, and to establish reference values for this population. The study sample consisted of 669 adults over 20 years old, 264 adolescents aged 12 to 19 years old and 391 children under 11 years old from both genders. The samples were collected at the end of 2007 and during 2008 in different city zones. Higher blood lead concentration was significantly associated with gender, smoking, offal intake, area of residence and age. The blood cadmium concentration was significantly associated with gender, smoking, consumption of distilled beverages and age. The reference values of lead and cadmium established for adults above 20 years old were 33 µg/L and 0.6 µg/L, respectively, for adolescents (12 to 19 years old) were 31 µg/L and 0.6 µg/L, respectively and for children under 11 years old were 29 µg/L and 0.2 µg/L, respectively. The results of this study indicate that the exposure levels of the investigated population to lead and cadmium are low.
Assuntos
Cádmio/sangue , Exposição Ambiental/estatística & dados numéricos , Poluentes Ambientais/sangue , Chumbo/sangue , Adolescente , Adulto , Brasil , Cádmio/normas , Criança , Exposição Ambiental/normas , Poluentes Ambientais/normas , Feminino , Humanos , Chumbo/normas , Masculino , Valores de Referência , Adulto JovemRESUMO
Proper assessment of soil cadmium (Cd) concentrations is essential to establish legislative limits. The present study aimed to assess background Cd concentrations in soils from the state of São Paulo, Brazil, and to correlate such concentrations with several soil attributes. The topsoil samples (n = 191) were assessed for total Cd contents and for other metals using the USEPA 3051A method. The background concentration was determined according to the third quartile (75th). Principal component analysis, Spearman correlation, and multiple regressions between Cd contents and other soil attributes (pH, cation exchange capacity (CEC), clay content, sum of bases, organic matter, and total Fe, Al, Zn, and Pb levels) were performed. The mean Cd concentration of all 191 samples was 0.4 mg kg(-1), and the background concentration was 0.5 mg kg(-1). After the samples were grouped by parent material (rock origin) and soil type, the background Cd content varied, i.e., soils from igneous, metamorphic, and sedimentary rocks harbored 1.5, 0.4, and 0.2 mg kg(-1) of Cd, respectively. The background Cd content in Oxisols (0.8 mg kg(-1)) was higher than in Ultisols (0.3 mg kg(-1)). Multiple regression demonstrated that Fe was primarily attributed to the natural Cd contents in the soils (R (2) = 0.79). Instead of a single Cd background concentration value representing all São Paulo soils, we propose that the concentrations should be specific for at least Oxisols and Ultisols, which are the primary soil types.
Assuntos
Cádmio/análise , Monitoramento Ambiental , Poluentes do Solo/análise , Solo/química , Brasil , Cádmio/normas , Análise Multivariada , Poluentes do Solo/normasRESUMO
The validation of an analytical method was carried out for the determination of cadmium (Cd) in fish. The method was based on sample digestion in a microwave oven and subsequent reading using an atomic absorption spectrometer with a graphite furnace. The factorial design of experiments was applied to assess method ruggedness using the methodology of Box et al. [Box GEP, Hunter WG, Hunter JS. 1978. Statistics for experiments: an introduction to design, data analysis and model building. New York (NY): Wiley], studying the influence of sample mass, volume and concentration of acid used for sample digestion and the volume of modifier used. To study the possible matrix effect in the determination of Cd, the standard addition method was also performed. The results were treated using the OLS method. For the normality test a homoskedastic distribution was observed for the developed method and the results were adjusted to the statistical model proposed. F-tests and Student's t-tests indicated that there was no matrix effect on the calibration curve between the concentration range 1.0-10.0 µg Cd l(-1). Parameters such as selectivity, precision, decision limit, detection capability and limit of quantification were established by the method of standard addition to blank samples. The limit of quantification was 6.8 µg kg(-1). Accuracy, which was evaluated by using a certified reference material, was 107.0%. The recovery of the spiked analyte was 93.69% for the concentration of 50 µg kg(-1). Precision was defined by the coefficient of variation observed (Horrat value), estimated in terms of repeatability and reproducibility, and the values were below the limit, which is 2.0. The validation procedure confirmed the suitability of the method.
Assuntos
Cádmio/análise , Contaminação de Alimentos/análise , Alimentos Marinhos/análise , Espectrofotometria Atômica/métodos , Animais , Brasil , Cádmio/normas , Peixes , Contaminação de Alimentos/estatística & dados numéricos , Limite de Detecção , Carne/análise , Micro-Ondas , Músculos/química , Padrões de Referência , Espectrofotometria Atômica/normasRESUMO
In the past, Cd regulations have imposed trade restrictions on foodstuffs from some developing countries seeking to access markets in the developed world and in recent years, there has been a trend towards imposing more rigorous standards. This trend seems to respond more to public and private sectors strategies in some developed countries to create disguised barriers to trade and to improve market competitiveness for their industries, than to scientifically justified health precautions (sanitary and phytosanitary measures) and/or technical barriers to trade acceptable under the Uruguay Round Agreement of the WTO. Applying more rigorous Cd standards in some developed countries will not only increase production costs in developing countries but it will also have a large impact on their economies highly dependent on international agricultural markets. In the current literature there are large uncertainties in the cause-effect relationship between current levels of Cd intakes and eventual health effects in human beings; even the risk of Cd to kidney function is under considerable debate. Recent works on the importance of zinc:Cd ratio rather than Cd levels alone to determine Cd risk factors, on the one hand, and on the declining trends of Cd level in foods and soils, on the other, also indicate a lack of scientific evidence justifying more restrictive cadmium standards. This shows that developing countries should fight for changing and making more transparent the current international structures and procedures for setting sanitary and phytosanitary measures and technical barriers to trade.
Assuntos
Cádmio/normas , Comércio/legislação & jurisprudência , Contaminação de Alimentos/legislação & jurisprudência , Indústria Alimentícia/legislação & jurisprudência , Legislação sobre Alimentos , Cádmio/toxicidade , Comércio/economia , Comércio/educação , Países em Desenvolvimento , Saúde Ambiental , Indústria Alimentícia/economia , Indústria Alimentícia/normas , Humanos , Legislação sobre Alimentos/economiaRESUMO
A method for the multielement determination of cadmium and lead in urine is proposed by simultaneous electrothermal atomic absorption spectrometry (SIMAAS) with an end-capped transversely heated graphite atomizer (EC-THGA). The best conditions for cadmium and lead determination were obtained in the presence of NH4H2PO4 as a chemical modifier, using 500 degrees C and 1800 degrees C as the pyrolysis and atomization temperatures, respectively. Urine samples were diluted 1 + 4 directly in autosampler cups with a mixture of 0.125% (w/v) Triton X-100 + 2.5% (v/v) HNO3 + 0.31% (w/v) NH4H2PO4. The optimized heating program was carried out in 57 s, and the instrument calibration was done with aqueous reference solutions. The use of EC-THGA increased the sensitivity of cadmium and lead by 14% and 25%, respectively. The detection limits (n = 20, 3delta) were 0.03 microg L(-1) (0.36 pg) for cadmium and 0.57 microg L(-1) (6.8 pg) for lead. The performance of EC-THGA was acceptable up to 500 heating cycles. The reliability of the entire procedure was checked with the analysis of a lyophilized urine certified reference material. The found concentrations were in agreement with the recommended values (95% confidence level).
Assuntos
Cádmio/urina , Chumbo/urina , Cádmio/normas , Temperatura Alta , Humanos , Chumbo/normas , Magnésio/química , Fosfatos/química , Reprodutibilidade dos Testes , Espectrofotometria Atômica/instrumentação , Espectrofotometria Atômica/métodosRESUMO
Esta norma establece el método para la determinación del cadmico por el método de la Ditizona I, es plicable para aguas en general.