Rodrigo Valdés

Increased Lung and Bladder Cancer Incidence in Adults after In Utero and Early-Life Arsenic Exposure

Background: From 1958 to 1970, >100,000 people in northern Chile were exposed to a well-documented, distinct period of high drinking water arsenic concentrations. We previously reported ecological evidence suggesting that early-life exposure in this population resulted in increased mortality in adults from several outcomes, including lung and bladder cancer. Methods: We have now completed the first study ever assessing incident cancer cases after early-life arsenic exposure, and the first study on this topic with individual participant exposure and confounding factor data. Subjects included 221 lung and 160 bladder cancer cases diagnosed in northern Chile from 2007 to 2010, and 508 age and gender-matched controls. Results: ORs adjusted for age, sex, and smoking in those only exposed in early life to arsenic water concentrations of ≤110, 110 to 800, and >800 μg/L were 1.00, 1.88 [95% confidence interval (CI), 0.96–3.71], and 5.24 (3.05–9.00; Ptrend < 0.001) for lung cancer, and 1.00, 2.94 (1.29–6.70), and 8.11 (4.31–15.25; Ptrend < 0.001) for bladder cancer. ORs were lower in those not exposed until adulthood. The highest category (>800 μg/L) involved exposures that started 49 to 52 years before, and ended 37 to 40 years before the cancer cases were diagnosed. Conclusion: Lung and bladder cancer incidence in adults was markedly increased following exposure to arsenic in early life, even up to 40 years after high exposures ceased. Such findings have not been identified before for any environmental exposure, and suggest that humans are extraordinarily susceptible to early-life arsenic exposure. Impact: Policies aimed at reducing early-life exposure may help reduce the long-term risks of arsenic-related disease. Cancer Epidemiol Biomarkers Prev; 23(8); 1529–38. ©2014 AACR.

Case-Control Study of Arsenic in Drinking Water and Kidney Cancer in Uniquely Exposed Northern Chile

Millions of people worldwide are exposed to arsenic in drinking water. The International Agency for Research on Cancer has concluded that ingested arsenic causes lung, bladder, and skin cancer. However, a similar conclusion was not made for kidney cancer because of a lack of research with individual data on exposure and dose-response. With its unusual geology, high exposures, and good information on past arsenic water concentrations, northern Chile is one of the best places in the world to investigate the carcinogenicity of arsenic. We performed a case-control study in 2007-2010 of 122 kidney cancer cases and 640 population-based controls with individual data on exposure and potential confounders. Cases included 76 renal cell, 24 transitional cell renal pelvis and ureter, and 22 other kidney cancers. For renal pelvis and ureter cancers, the adjusted odds ratios by average arsenic intakes of <400, 400-1,000, and >1,000 µg/day (median water concentrations of 60, 300, and 860 µg/L) were 1.00, 5.71 (95% confidence interval: 1.65, 19.82), and 11.09 (95% confidence interval: 3.60, 34.16) (Ptrend < 0.001), respectively. Odds ratios were not elevated for renal cell cancer. With these new findings, including evidence of dose-response, we believe there is now sufficient evidence in humans that drinking-water arsenic causes renal pelvis and ureter cancer.

Latitudinal Analysis of Rainfall Intensity and Mean Annual Precipitation in Chile

El estudio y analisis de las precipitaciones se ha convertido en una herramienta vital para conocer el comportamiento temporal y espacial del recurso hidrico, tanto en terminos de disponibilidad, asi como de los posibles impactos asociados a los eventos extremos. El objetivo de esta investigacion fue evaluar las intensidades maximas (duracion D = 1 h y periodos de retorno T = 5 y 100 anos) y los montos anuales de precipitacion para diferentes latitudes y zonas climaticas de Chile, analizando la informacion de miles de bandas pluviograficas y la pluviometria anual de 49 estaciones de medicion. Ello, porque aun no es claro que las intensidades de precipitacion difieren latitudinalmente en el pais, asi como lo hacen los montos anuales de las lluvias. Asimismo, no hay evidencia cientifica de los rangos y montos de ambas variables. Asi, se utilizo la funcion de Gumbel y formulas matematicas para desarrollar las curvas intensidad-duracion-frecuencia (IDF) de cada estacion. Los valores minimos y maximos de intensidad de precipitacion registrados para T = 100 anos, fueron 8,79 (zona hiperarida) y 40,17 mm h-1 (zona subhumeda-humeda). Respecto al monto anual de precipitaciones, los valores minimos y maximos fueron 43,9 (zona hiperarida) y 3891,0 mm ano-1 (zona humeda) respectivamente. Adicionalmente, la intensidad maxima real registrada en cada estacion fue analizada para determinar su probabilidad de excedencia. Asimismo, se realizaron comparaciones multiples para detectar diferencias significativas entre las estaciones de medicion y las diferentes zonas climaticas, mediante el test no parametrico Kruskal Wallis (alfa = 0,05). Las diferencias entre los valores maximos y minimos registrados en la totalidad de las estaciones analizadas pueden superar las 80 veces, para el caso de los montos anuales de las lluvias, y pueden llegar hasta 4,5 veces para el caso de las intensidades de precipitacion (T = 100 anos). Sin embargo, se encontraron valores maximos similares de intensidad de precipitacion en diferentes latitudes y altitudes del territorio nacional. Por tanto, se concluye que un mayor monto anual de lluvia no necesariamente involucra una mayor intensidad de precipitacion

Respiratory disease and particulate air pollution in Santiago Chile: contribution of erosion particles from fine sediments.

Air pollution in Santiago is a serious problem every winter, causing thousands of cases of breathing problems within the population. With more than 6 million people and almost two million vehicles, this large city receives rainfall only during winters. Depending on the frequency of storms, statistics show that every time it rains, air quality improves for a couple of days, followed by extreme levels of air pollution. Current regulations focus mostly on PM10 and PM2.5, due to its strong influence on respiratory diseases. Though more than 50% of the ambient PM10s in Santiago is represented by soil particles, most of the efforts have been focused on the remaining 50%, i.e. particulate material originating from fossil and wood fuel combustion, among others. This document emphasizes the need for the creation of erosion/sediment control regulations in Chile, to decrease respiratory diseases on Chilean polluted cities.

Basal cell carcinoma appearing in a facial nevus sebaceous of Jadassohn: dermoscopic features

The nevus sebaceous of Jadassohn usually affects the face or scalp. It tends to evolve in three stages, and the final stage is characterized by the appearance of tumours. We present the case of a facial nevus sebaceous of Jadasshon in which a basal cell carcinoma developed. We also explore the diagnosis of this disease, which was established through dermoscopy, and propose using this technique in the clinical follow-up of this type of hamartoma, thereby allowing the early detection of cancer development.

Argyria mimicking a blue nevis: dermoscopy features

Argyria is a rare disease caused by prolonged skin contact with silver. Localized cases have been described regarding the use of topical medications, and trauma with objects containing this metal such as acupuncture needles and jewelry. Clinically, a macule or a patch, round or oval, appears in the infected area, with a characteristic bluey-gray color. To our knowledge this is the first time that this clinical condition has been described through the use of dermoscopy.

HARVEST LABOR QUALITY AND PRODUCTIVITY:CASE STUDY OF CHERRY GROWING IN CHILE

In Chile, the cherry tree has been one of the fastest growing and most profitable crops in the last ten years. However, increasing production costs, the scarcity of hired labor, and unfavorable exchange rates have reduced the productivity and competitiveness of the Chilean fruit sector. The aim of this article is to evaluate the harvest labor quality in cherry growing in Chile through the use of productivity indicators. A harvest labor evaluation system (HLES) was designed and four indicators were measured: Average Weight of Harvested Box, Average Daily Production per Worker, Percent of Export Fruit, and Percent of Fruit Discarded. Significant differences werefound between the 2010/11 season (with the HLES implementation) and the previous seasons without HLES. The average worker yield, average weight of a filled box, and fruit quality improved, while the amount of discarded fruit decreased. Hired labor management in agriculture is crucial for improving the productivity of the fresh fruit export producers. The use of HLES and the adoption of new technologies could help to solve the competitiveness problem in the Chilean fruit sector.