Ambient air pollution is associated with the increased incidence of breast cancer in US.

Women in the United States have among the highest incidence rates of breast cancer. The reasons behind this are not fully understood. In this study we analyzed US ecological data to examine the effect of ambient air pollution on breast cancer incidence. Time trends and regional variations in breast cancer incidence were assessed in relation to emissions of air pollutants. A statistically significant increase in the incidence of female breast cancer in US was observed during 1986-2002, which could occur following the increased emissions of air pollutants as a result of industrial development and automobile use. Emissions of nitrogen oxides, carbon monoxide, sulfur dioxide, and volatile organic compounds were shown to be positively associated with breast cancer incidence with r = 0.89, 0.82, 0.71, and 0.68, respectively (p < 0.001). A higher incidence rate of breast cancer was found in high emission regions and metropolitan areas. This study suggests a possible association between air pollution and female breast cancer in US.

Correlation of white female breast cancer incidence trends with nitrogen dioxide emission levels and motor vehicle density patterns.

The long-term trend of female breast cancer incidence rates in the United States and some European countries demonstrates a similar pattern: an increasing trend in the last century followed by a declining trend in this century. The well-known risk factors cannot explain this trend. We compared the breast cancer incidence trends obtained from SEER data with the trend of nitrogen dioxides (NOx) emission and monitoring data as well as motor vehicle density data. The upward followed by downward trend of NOx is similar to the breast cancer incidence trend but with an offset of 20 years earlier. Motor vehicles are the major source of NOx emissions. The geographic distribution of motor vehicles density in 1970 in the observed US counties is positively correlated with breast cancer incidence rates (R(2) 0.8418, the correlation coefficient = 0.9175) in 1980-1995. Because both the time trend and geographic pattern are associated with breast cancer incidence rates, further studies on the relationship between breast cancer and air pollution are needed.

Mood and neurobehavioral correlates of cerebellar lesions.

OBJECTIVE: The authors studied mood disorder and neurobehavioral correlates of solitary focal cerebellar (CB) lesions. BACKGROUND: CB function has been correlated with cognitive, behavioral, and psychiatric conditions. Systematic study of uncomplicated CB pathology can further our understanding of these correlates. METHOD: Magnetic Resonance Images were blindly selected from 20,000 scans for solitary focal CB lesions after excluding other pathology. "Secondary" conditions (developing after lesion onset) were determined using structured clinical interviews (DIS and SCID) for psychiatric diagnoses while blind to MRI findings. Clinical correlates of lesions and a priori hypotheses were examined in 13 participants while controlling for alternative attributions (atrophy, hyperintensities, ventriculomegaly, disability, etc.). RESULTS: Bipolar disorders after CB lesions were more common than expected in normal populations (OR 28.62, 95% CI 3.51 < - >233.34, P=0.0001), replicating a previous finding. Secondary DSM-III and -IV depressive disorders correlated with posterolateral lesions of the right CB posterior lobe (P=0.0035); severity correlated with lesion size. Other lesion correlates included hypomania (anterolateral left CB posterior lobe), apathy (medial left anterior lobe, anterolateral right posterior lobe), disinhibition and dysexecution (medial left anterior lobe), agitation (central left and anterolateral right posterior lobe), and elation (anterolateral right posterior lobe). Although other structural cerebral and psychosocial variables did not explain the findings, much larger sample sizes will be needed to adequately control for these variables. CONCLUSIONS: Review of the literature reveals support for these findings, suggesting CB control of mood, behavior, and frontal cognition.

Lung adenocarcinoma incidence rates and their relation to motor vehicle density.

BACKGROUND AND OBJECTIVE: The temporal trend of adenocarcinoma incidence rates of the lung (ADL) has been reported to parallel the trend of nitrogen oxide (NOx) emissions in the United States. This study explores the geographic pattern of ADL incidence and its relation to motor vehicle density, the major indicator of NOx emissions before 1970. METHODS: ADL incidence rates by counties were retrieved from the nine sites of Surveillance, Epidemiology, and End Results (SEER) Program for the period of 1973 to 1990. Motor vehicle densities by county in 1970 for these SEER sites were estimated according to the numbers of motor vehicle registration and the size of each county. Regression analysis was done with the data of motor vehicle density by counties. RESULTS: A dose-response pattern between motor vehicle density and ADL incidence was found. The risks are 136% and 68% higher for ADL and squamous cell carcinoma, respectively, for male residents living in areas with 937 motor vehicles per square mile, compared with those living in areas with about one motor vehicle per square mile. The R2 are as high as 0.805 and 0.504 in regressions for male incidence rates of ADL and squamous cell carcinoma, respectively, with the vehicle density values. As a comparison, the prostate cancer incidence rates did not show dose-response relationship with motor vehicle density. If the effect of NOx emissions on ADL incidence rates can be proved by further studies, the current standard of allowance of NOx emissions may need to be revised.

Time trend and geographic patterns of lung adenocarcinoma in the United States, 1973-2002.

OBJECTIVE: To find the major factor explaining the substantial increase in incidence of adenocarcinoma of the lung (ADL), we observed its temporal trend, distributions in geographic areas and populations, and compared them with the distributions of air pollution and low-tar cigarette consumption in time, place, and populations. METHODS: The temporal and spatial patterns of ADL were compared with the level of nitrogen oxides (NO(x)) emissions as well as the use of low-tar cigarettes. RESULTS: Similar increasing trends followed by declining trends were seen in emission levels of NO(x) and ADL incidence rates. These trends peak about 20 years earlier for NO(x) levels than for ADL incidence. Incidence rates of ADL in high NO(x) emission areas were substantially higher than those in low NO(x) emission areas. Incidence rates of ADL in Black males are about 50% higher than in White males and can be explained by the differences in air quality related to residence site and size. CONCLUSIONS: The descriptive epidemiologic data help generate the hypothesis that long-term exposure to low-dose NO(x) may play a major role in causing steep increases in past ADL incidence rates. There is an urgent need to conduct further studies to determine whether the association is a causal relationship between long-term, low-dose exposure to NO(x) and ADL.

Declining incidence rate of lung adenocarcinoma in the United States.

BACKGROUND: Adenocarcinoma of the lung (ADL) increased worldwide during the last half century. We now report that a continuous decline of ADL began in the United States in 1999. METHOD: Incidence rates of ADL and squamous cell carcinoma of the lung (SQL) from The Surveillance Epidemiology and End Results Program were reviewed for the 31-year period beginning in 1973. The low-tar cigarette (tar 200% in women. From 1999 through 2003, the rate declined 14% in men and 8% in women. An analysis of age-specific incidence rates of ADL according to birth cohort demonstrates that rates declined progressively among persons born after 1934 for both genders. The increase in low-tar cigarette consumption did not precede the increase in ADL incidence rates, and the decline of ADL incidence after 1998 occurred without a preceding decline of low-tar cigarette consumption. CONCLUSION: Since 1999, the ADL incidence has declined. The temporal trend of ADL incidence may suggest that air pollution could be the possible determining cause for the trend. Increasing use of low-tar cigarettes in the United States and the decline in environmental tobacco smoke may be contributors but are less likely to be the driving force.