Assessing the Committed Effective Dose From 226Ra in Thermal Spring Water From San Diego De Alcala, Chihuahua, Mexico.

The oral administration of mineral-rich spring water is known as hydropinic treatment and is used to treat certain ailments. Health benefits are attributed to thermal spring water containing radioactive elements such as radium; this has popularized use of such radioactive water in various parts of the world, causing those who ingest it to increase their internal radiation dose. The goal of this study was to assess the activity concentrations of Ra present in the thermal spring waters of San Diego de Alcala, in the state of Chihuahua, Mexico, and to estimate the health risk posed to patients by the effective dose received from ingesting this water during hydropinic treatments. Water samples were taken from different areas of the San Diego de Alcala thermal springs, and pH, temperature, electrical conductivity, and total dissolved solids were measured. The Ra activity concentrations were measured with a liquid scintillation counter. The activity concentrations of Ra in sampled water varied from 125 to 452 mBq L with an average of 276 ± 40 mBq L. The committed effective dose from each of the Ra activity concentrations found in samples ranged from 9.80 × 10 to 4.0 × 10 mSv for hydropinic treatments being carried out in San Diego de Alcala thermal spring spas. Different treatments had different intake rates (200, 600, 1,000, and 1,500 mL d) and occurred over periods of 2 or 3 wk. According to the guidelines of the US Environmental Protection Agency, the maximum permissible amount of radium in drinking water is 185 mBq L; the Ra content in most of the collected samples exceeded this limit. The committed effective doses varied with Ra concentration and intake rate; none exceeded the World Health Organization's reference dose for drinking water of 0.1 mSv y, which is the maximum amount to which the population should be exposed.

[Skin cancer incidence in Zacatecas]. / Incidencia de cáncer de piel en Zacatecas.

BACKGROUND: Skin cancer is the most frequent cancer related to ultraviolet radiation. The aim was to estimate the incidence of skin cancer type, melanoma and non-melanoma in Zacatecas, Mexico. METHODS: An epidemiological study was carried out during the period from 2008 to 2012. The data were obtained from the Instituto Mexicano del Seguro Social (IMSS), Instituto de Seguridad y Servicios Sociales de los Trabajadores del Estado (ISSSTE), Secretaría de Salud de Zacatecas (SSZ) and a private source, the Centro Médico Alameda. The incidence and the global prevalence were estimated. RESULTS: We studied 958 skin cancer cases, histopathologically confirmed. The cases were distributed as: 63.6 % basal cell carcinomas, 25.8 % squamous cell carcinomas, and 10.6 % melanoma. Significantly higher proportions were observed in women in the basal cell carcinomas (60.4 %) and squamous cell carcinomas (53.4 %). However, in the case of melanoma, the major proportion was observed in men (55.9 %). The more frequent skin cancer location was the face and for basal cell carcinoma was the nose (53 %); for squamous cell carcinomas were the lips (36 %), and for melanoma it was also the nose (40 %). The skin cancer incidence was estimated in 20 cases for each 100 000 inhabitants. Linear regression analysis showed that the skin cancer is increasing at an annual rate of 10.5 %. CONCLUSIONS: The anatomical location indicates that solar UV radiation is a risk factor, since the face is the zone with major exposure to solar radiation.

INTRODUCCIÓN: el cáncer de piel es una neoplasia relacionada con la radiación ultravioleta solar. El objetivo fue estimar la incidencia del cáncer de piel de tipo melanoma y no-melanoma. MÉTODOS: se llevó a cabo un estudio epidemiológico entre 2008 y 2012 en Zacatecas, México. La información se obtuvo de los registros confirmados de cáncer de piel en el Instituto Mexicano del Seguro Social, el Instituto de Seguridad y Servicios Sociales de los Trabajadores del Estado, la Secretaría de Salud de Zacatecas y el laboratorio privado del Centro Médico Alameda. Se calculó la incidencia y la prevalencia global. RESULTADOS: se estudiaron 958 casos de cáncer de piel: 63.6 % de carcinoma basocelular, 25.8 % de espinocelular y 10.6 % de melanoma. Se observó una mayor prevalencia de mujeres: 60.4 % en carcinoma basocelular y 53.4 % en carcinoma espinocelular. En el melanoma prevalecieron los hombres (55.9 %). La región anatómica donde predominó el cáncer de piel fue la cara: la nariz (53 %) en carcinoma basocelular, los labios (36 %) en carcinoma espinocelular y la nariz (40 %) en melanoma. La incidencia estimada fue 20 casos por cada 100 000 habitantes. El análisis de regresión lineal mostró que el cáncer de piel se incrementa 10.5 % anualmente. Conclusiones: la ubicación de las lesiones sugiere que un factor de riesgo es la exposición a los rayos solares UV.