Gastric and colorectal cancer mortality in an urban and industrialized area of Brazil

Residential proximity to industrial pollution sources and colorectal cancer risk: A multicase-control study (MCC-Spain)

BACKGROUND

Colorectal cancer is the third most frequent tumor in males and the second in females worldwide. In Spain, it is an important and growing health problem, and epidemiologic research focused on potential risk factors, such as environmental exposures, is necessary.

OBJECTIVES

To analyze the association between colorectal cancer risk and residential proximity to industries, according to pollution discharge route, industrial groups, categories of carcinogens and other toxic substances, and specific pollutants released, in the context of a population-based multicase-control study of incident cancer carried out in Spain (MCC-Spain).

METHODS

MCC-Spain included 557 colorectal cancer cases and 2948 controls in 11 provinces, frequency matched by sex, age, and region of residence. Distances were computed from subjects' residences to each of the 134 industries located in the study area. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (95%CIs) for categories of distance (from 1 km to 3 km) to industrial facilities, adjusting for matching variables and other confounders.

RESULTS

Excess risk (OR; 95%CI) of colorectal cancer was detected near industries overall for all distances analyzed, from 1 km (2.03; 1.44-2.87) to 3 km (1.26; 1.00-1.59). In general, industries releasing pollutants to air showed higher excess risks than facilities releasing pollution to water. By industrial sector, excess risk (OR; 95%CI) was found near (≤3 km) production of metals (2.66; 1.77-4.00), surface treatment of metals (1.48; 1.08-2.02), glass and mineral fibers (2.06; 1.39-3.07), organic chemical industry (4.80; 3.20-7.20), inorganic chemical industry (6.74; 4.38-10.36), food/beverage sector (3.34; 2.38-4.68), and surface treatment using organic solvents (6.16; 4.06-9.36). By pollutants, the main excess risks (OR; 95%CI) were found near (≤3 km) industries releasing nonylphenol (9.19; 5.91-14.28), antimony (5.30; 3.45-8.15), naphthalene (3.11; 2.16-4.49), organotin compounds (2.64; 1.76-3.98), manganese (2.53; 1.63-3.93), dichloromethane (2.52; 1.74-3.66), and vanadium (2.49; 1.59-3.91).

CONCLUSIONS

Our results support the hypothesis that residing in the proximity of industries may be a risk factor for colorectal cancer.

Cancer mortality in towns in the vicinity of installations for the production of cement, lime, plaster, and magnesium oxide

Our objective was to investigate whether there might be excess cancer mortality in the vicinity of Spanish installations for the production of cement, lime, plaster, and magnesium oxide, according to different categories of industrial activity. An ecologic study was designed to examine municipal mortality due to 33 types of cancer (period 1997-2006) in Spain. Population exposure to pollution was estimated on the basis of distance from town to industrial facility. Using spatial Besag-York-Mollié regression models with integrated nested Laplace approximations for Bayesian inference, we assessed the relative risk of dying from cancer in a 5-km zone around installations, analyzed the effect of category of industrial activity according to the manufactured product, and conducted individual analyses within a 50-km radius of each installation. Excess all cancer mortality (relative risk, 95% credible interval) was detected in the vicinity of these installations as a whole (1.04, 1.01-1.07 in men; 1.03, 1.00-1.06 in women), and, principally, in the vicinity of cement installations (1.05, 1.01-1.09 in men). Special mention should be made of the results for tumors of colon-rectum in both sexes (1.07, 1.01-1.14 in men; 1.10, 1.03-1.16 in women), and pleura (1.71, 1.24-2.28), peritoneum (1.62, 1.15-2.20), gallbladder (1.21, 1.02-1.42), bladder (1.11, 1.03-1.20) and stomach (1.09, 1.00-1.18) in men in the vicinity of all such installations. Our results suggest an excess risk of dying from cancer, especially in colon-rectum, in towns near these industries.

Geospatial disparities and the underlying causes of major cancers for women in Taiwan

Some specific types of cancer still pose a severe threat to the health of Taiwanese women. This study focuses on determining the geographical locations of hot spots and causal factors related to the major categories of cancers in Taiwanese women. Cancer mortality data from 1972 to 2001 of 346 townships in Taiwan were obtained from the Atlas of Cancer Mortality. Principal component analysis was conducted to determine the primary categories of female cancers. The spatial patterns of hot spots and cold spots for each major cancer category were identified using the local indicator of spatial association. Finally, the regional differences between the hot spots and cold spots were compared to confirm the possible factors causing cancer throughout Taiwan. A total of 21 cancer types in women were divided into seven major categories, which accounted for 68.0% of the total variance. The results from the spatial autocorrelation analysis showed significant spatial clusters of the cancer categories. Based on the overall consistency of results between this study and those of previous research, this study further identified the high-risk locations and some specific risk factors for major cancer types among Taiwanese women.

Effectiveness of whole grain consumption in the prevention of colorectal cancer: meta-analysis of cohort studies

The present work aimed to evaluate the effectiveness of whole grain consumption in preventing colorectal cancer. A systematic review with meta-analysis of 11 cohort studies was carried out. The age group of the population studied (1,719,590 participants) was between 25 and 76 years of age. The review evaluated the relative risks with the Cox proportional hazard model. The period of study varied from 6 to 16 years, where 7,745 persons developed colorectal cancer during the follow-up period. In the multivariate analysis, the highest quintile relative risk was 0.94 (95% confidence interval, 0.85-1.03), whereas that for the lowest quintile was 0.96 (95% confidence interval, 0.88-1.04). The location of tumors was also evaluated, with tumors in the colon demonstrating a relative risk of 0.93 (95% confidence interval, 0.83-1.02) and tumors in the recto a relative risk equal to 0.89 (95% confidence interval, 0.79-1.00). In this multivariate analysis, consumption of whole grains was inversely associated with the risk of developing colorectal cancer.

Mortality in the bedouin population and proximity to a regional industrial complex

BACKGROUND

The study was initiated by public concern about exposure to an industrial park (IP) emission. The study examined whether mortality in the Bedouin population in the southern part of Israel is associated with the residential distance to the IP.

MATERIAL AND METHODS

Ecological study during 1995-2001 included the entire Bedouin population. Mortality data was obtained from the Central Bureau of Statistics. As an indirect measurement of exposure we used residential distance to the IP (with 20 km radius as a cut-of-point) based on residents' complaints about odor related to the IP. Differences in mortality rates by distance were assessed by the Mantel-Haenszel relative risk (M-H RR) within the 95% CI. The country Arab population served as a reference for calculation of the age-adjusted standardized mortality ratio (SMR).

RESULTS

Increased mortality rates due to symptoms/ill-defined conditions and non-external causes were observed in the Bedouin population of both sexes, residing up to 20 km from the IP, compared to those living in more remote areas. Corresponding M-H RR (plus 95% CI) were 1.66 (1.17-2.36), 1.24 (1.06-1.44) in females, and 1.55 (1.15-2.10), 1.32 (1.15-1.52) in males.

CONCLUSIONS

The study results suggest an association between residential proximity to the regional IP and increased mortality rates in the Negev Bedouin population. These findings have been accepted by the authorities as an issue for community health protection.

Air pollution impact assessment on agroecosystem and human health characterisation in the area surrounding the industrial settlement of Milazzo (Italy): a multidisciplinary approach

In order to evaluate the impact of atmospheric pollutants emitted by the industrial settlement of Milazzo (Italy) on agriculture, sulphur dioxide and ozone levels in air were monitored and the data were used to estimate yield losses of the most widespread cultures. Trace element concentrations in crops and soils were also detected and metabolic profiles of soil microbial communities were considered. Vibrio fischeri test was used to appraise airborne pollutant ecotoxicity and epidemiological studies on causes of death distribution were carried out to characterize health state of people living in the area. All the sampling points were selected in farms on the basis of a theoretical meteo-diffusive model of industrial air pollutants. Experimental SO2 and O3 values mainly exceeded the threshold established by Italian and EU regulations to protect vegetation and they correspond to estimated significant crop losses. Conversely toxic element residues in soils and in agroalimentary products were generally lower than the fixed values. SO2 and O3 concentrations, toxic element contents and ecotoxicity levels of airborne pollutants were not related only to industrial site emissions, while the fluctuations on metabolic profiles of soil microbial communities seem to agree with the predicted deposition of xenobiotic compounds from the industrial plants. The epidemiological study evidenced a better health state of populations living in the investigated area than in the Messina province and the Sicily region but, inside the area, males living in the municipalities closest to the industrial settlement exhibited a worst health state than those in the very far ones.

Environment and cancer in Brazil: an overview from a public health perspective

This paper presents the current pattern of cancer incidence in Brazil by analyzing the country's cancer epidemiological profile. The authors highlight the observed overlapping distribution of cancer incidence in Brazil in tumor sites normally associated with higher socioeconomic status (cancers of the breast, prostate, and colon/rectum, among others) and poverty (cervix, stomach, oral cavity, and penis). In addition to analyzing the demographic and social characteristics associated with current epidemiological distribution of cancer in Brazil, the authors present several of the most important environmental risk factors (smoking and exposure to radiation, pesticides, and other chemicals) and discuss their respective exposure levels in the Brazilian context. The article concludes with an evaluation of the principal challenges facing environmental cancer control programs in Brazil, particularly focusing on smoking and exposure to chemicals.

Aberrant crypt foci and colon cancer: comparison between a short- and medium-term bioassay for colon carcinogenesis using dimethylhydrazine in Wistar rats

Aberrant crypt foci (ACF) in the colon of carcinogen-treated rodents are considered to be the earliest hallmark of colon carcinogenesis. In the present study the relationship between a short-term (4 weeks) and medium-term (30 weeks) assay was assessed in a model of colon carcinogenesis induced by dimethylhydrazine (DMH) in the rat. Six-week-old male Wistar rats were given subcutaneous injections of DMH (40 mg/kg) twice a week for 2 weeks and killed at the end of the 4th or 30th week. ACF were scored for number, distribution pattern along the colon and crypt multiplicity in 0.1% methylene-blue whole-mount preparations. ACF were distinguished from normal crypts by their larger size and elliptical shape. The incidence, distribution and morphology of colon tumors were recorded. The majority of ACF were present in the middle and distal colon of DMH-treated rats and their number increased with time. By the 4th week, 91.5% ACF were composed of one or two crypts and 8.5% had three or more crypts, while by the 30th week 46.9% ACF had three or more crypts. Thus, a progression of ACF consisting of multiple crypts was observed from the 4th to the 30th week. Nine well-differentiated adenocarcinomas were found in 10 rats by the 30th week. Seven tumors were located in the distal colon and two in the middle colon. No tumor was found in the proximal colon. The present data indicate that induction of ACF by DMH in the short-term (4 weeks) assay was correlated with development of well-differentiated adenocarcinomas in the medium-term (30 weeks) assay.