Niveles de cromo y alteraciones de salud en una población expuesta a las actividades de curtiembres en Bogotá, Colombia / Chromium levels and their relationship with alterations in the health of tannery workers living and working in Bogotá, Colombia

Objetivo Determinar si los niveles de cromo en orina están más altos de los permitidos y contrastarlos con alteraciones de salud en personas del barrio San Benito en Bogotá. Métodos En una muestra de 827 personas, se cuantificó cromo total en orina como biomarcador de exposición y se contrastó con alteraciones de salud atribuibles a exposición a cromo. La exposición se definió, por la "Ocupación actual" relacionada con la labor en curtiembres. Se definieron dos estratos: "Directamente expuestos" 26 por ciento y "Potencial alta exposición" 73 por ciento. Resultados Un 6,3 por ciento presentó niveles de cromo >10 ug/L (intervalo de confianza: 4,64-7,96 por ciento). No se encontraron diferencias estadísticamente significativas entre los dos estratos. El 34,3 por ciento presentó diagnósticos posiblemente atribuibles a la exposición a cromo. El 23,3 por ciento otorrinolaringológico; 6,5 por ciento dermatológico; 2,9 por ciento oftalmológico; 1,6 por ciento cavidad oral y el 65,7 por ciento no relacionados. Se halló asociación entre niveles >10ug/L y residir en la zona (OR 4,94 IC:1,2- 20,7 por ciento). Los resultados sugieren asociación entre ocupación y alteraciones de salud atribuibles a la exposición a compuestos de cromo. Conclusiones Las personas que participan del proceso productivo del cuero tienen un riesgo significativo de presentar hallazgos clínicos posiblemente atribuibles a la exposición a cromo, OR 4,33 (3,12-6,02). La población general se esta viendo expuesta de manera no diferente a aquella con ocupación relacionada con las curtiembres, lo que puede deberse a que los habitantes del sector están en contacto con cromo o compuestos por vías diferentes a la ocupacional, como contaminación ambiental.

Objective Determining whether chromium levels in urine samples were higher than limits and contrasting them with alterations in the health of people living and working in the San Benito neighbourhood of Bogotá. Methods The total amount of chromium in urine was measured as a biological marker of exposure in a sample of 827 people. This was contrasted with health alterations attributed to chromium exposition. Exposure was defined by being whether current economic activity was related to working in a tannery. Two groups were defined: being directly exposed (26 percent) and having potentially high exposure (73 percent). Results 6.3 percent presented >10 ug/L chromium levels (4.64 percent to 7.96 percent confidence interval). No significant statistical differences were found between both groups. 34.3 percent presented a diagnosis of possible attribution to chromium exposure, of whom 23.3 percent were due to otorhinolaryngologic issues, 6.5 percent to dermatological ones, 2.9 percent to ophthalmologic ones and 1.6 percent to oral cavity issues. The remaining 65.7 percent of cases were not related. >10ug/L levels and living in the particular neighbourhood in question were associated (4.94 odds ratio; 1.18 percent-20.69 percent CI). The results suggested a connection between economic activity and health alterations due to chromium components. Conclusions The people involved in producing leather have a significant risk of presenting clinical conditions attributed to chromium exposure (4.33 OR; 3.12-6.02 CI). San Benito´s inhabitants are being exposed to chromium as if they were actually working in a tannery as they are in daily contact with chromium or its components through non work-related activities, such as environmental contamination. Concern at such exposure should lead to further in-depth studies.

Uso do chumbo em urina como indicador de exposição e sua relação com chumbo no sangue / Use of urine lead level as an exposure indicator and its relationship to blood lead

O objetivo deste trabalho foi verificar se há correlação estatisticamente significativa entre as concentrações de chumbo no sangue (Pb-S) e urina (Pb-U). A espectrometria de absorção atômica eletrotérmica foi utilizada na determinação da concentração de chumbo no material biológico. As amostras de sangue e de urina foram coletadas entre trabalhadores expostos ocupacionalmente (95) e entre adultos (130) e crianças até 15 anos (22) expostos ambientalmente. Após um teste que mostrou diferenças significativas entre Pb-U e as três categorias previamente determinadas, pontos de corte em Pb-U puderam ser fixados para a predição dos valores de Pb-S pela curva ROC. Assim, para Pb-U até 0,55 µg.dL-1, pode-se esperar que Pb-S seja menor do que 10 µg.dL-1, ao passo que níveis de chumbo no sangue até 27,6 µg.dL-1 são esperados quando o teor do metal na urina é menor do que 2,05 µg.dL-1. Logo, a urina pode ser utilizada em substituição ao sangue para avaliação da exposição ocupacional ao chumbo. Contudo, recomenda-se cautela no caso da exposição ambiental, devendo-se utilizar o chumbo urinário como uma estimativa do conteúdo do metal no sangue.

The aim of this work was to verify whether there are statistically significant correlation between the concentrations of lead in blood (Pb-B) and urine (Pb-U). Electrothermal atomic absorption spectrometry was used in the determination of lead concentration in biological material. Venous blood and spot urine were collected from workers occupationally exposed (95), adults (130) and children up to 15 years old (22) environmentally exposed. After a test showing significant differences between Pb-U and the three categories previously determined, cutting points for Pb-U were established to predict Pb-B values by the ROC curve. Thus, it is expected that Pb-B is lower than 10 µg.dL-¹ with Pb-U up to 0.55 µg. dL-¹, whereas lead levels in blood below 27.6 µg. dL-¹ are expected when the amount of the metal in urine is lower than 2.05 µg.dL-¹. So, urine can be used to replace blood for the assessment of the occupational exposure to lead. However, caution is advised in the case of environmental exposure, since urinary lead should be used just as an estimation of the metal content in blood.