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ObjectiveTo evaluate exposure–response between 1,3-butadiene, styrene and lymphohaematopoietic cancers in an updated cohort of workers at six North American plants that made synthetic rubber polymers.MethodsEmployees were followed from 1943 through 2009 to determine mortality outcomes. Cox regression analyses estimated rate ratios (RRs) and 95% CIs by quartile of cumulative exposure to butadiene or styrene, measured in parts per million-years (ppm-years), and exposure–response trends for all leukaemia, lymphoid leukaemia, myeloid leukaemia, acute myeloid leukaemia, non-Hodgkin’s lymphoma (NHL), multiple myeloma and all B-cell malignancies.ResultsAmong 21 087 workers, adjusted RRs for butadiene and all leukaemia (132 deaths) rose with increasing exposure, with an RR of 2.53 (95% CI 1.37 to 4.67) in the highest exposure quartile (≥363.64 ppm-years), and the exposure–response trend was statistically significant for all leukaemia (p=0.014) and for lymphoid leukaemia (52 deaths, p=0.007). Styrene exposure–response trends for all leukaemia and lymphoid leukaemia were less consistent than those for butadiene. Cumulative exposures to butadiene and styrene were not associated consistently with myeloid leukaemias or the B-cell malignancies, NHL and multiple myeloma.ConclusionsWe confirmed a positive exposure–response relationship between butadiene and all leukaemia among workers, most of whom had coexposure to styrene. Results supported an association between butadiene and lymphoid leukaemia, but not myeloid leukaemia, and provided little evidence of any association of butadiene or styrene exposures with major subtypes of B-cell malignancies other than lymphoid leukaemia, including NHL and multiple myeloma.

Objective – To evaluate exposure-response relationships between 1,3-butadiene and styrene and selected diseases among synthetic rubber polymer workers. Methods – 21,087 workers (16,579 men; 4508 women) were followed from 1943 through 2009 to determine mortality outcomes. Cox regression models estimated rate ratios (RRs) and 95% confidence intervals (CIs) by quartile of cumulative exposure to butadiene or styrene and exposure-response trends for cancers of the bladder, lung, kidney, esophagus and pancreas, and for all nonmalignant respiratory disease (NMRD), chronic obstructive pulmonary disease (COPD) and pneumonia. Results – Bladder cancer RRs were 2.13 (95% CI = 1.03 to 4.41) and 1.64 (95% CI = 0.76 to 3.54) in the highest quartiles of cumulative exposure to butadiene and styrene, respectively, and exposure-response trends were positive for both monomers (butadiene, trend p = 0.001; styrene, trend p = 0.004). Further analyses indicated that the exposure-response effect of each monomer on bladder cancer was demonstrated clearly only in the subgroup with high cumulative exposure (at or above the median) to the other monomer. Lung cancer was not associated with either monomer among men. Among women, lung cancer RRs were above 1.0 in each quartile of cumulative exposure to each monomer, but exposure-response was not seen for either monomer. Male workers had COPD RRs slightly above 1.0 in each quartile of cumulative exposure to each monomer, but there was no evidence of exposure-response among the exposed. Monomer exposure was not consistently associated with COPD in women or with the other cancer outcomes. Conclusions – This study found a positive exposure-response relationship between monomer exposures and bladder cancer. The independent effects of butadiene and styrene on this cancer could not be delineated. In some analyses, monomer exposure was associated with lung cancer in women and with COPD in men, but inconsistent exposure-response trends and divergent results by sex do not support a causal interpretation of the isolated positive associations.

OBJECTIVE The aim of this study was to characterize environmental exposure from Deepwater Horizon oil spill among pre-K to fourth-grade children from six schools in Mobile County, Alabama. METHODS A mail-in survey administered 11 months post-oil spill to children's parents/caregivers elicited information on exposure-related activities. Descriptive and multivariable analyses were performed. RESULTS Overall, 180 children (coastal schools, 90; inland schools, 90) completed the survey. During the post-oil spill period, children in coastal schools were less likely to reduce their exposure-related activities, including fishing; eating and selling caught fish; visiting beaches; and parental participation in cleanup activities, than children in inland schools. Particularly, fishing and eating caught fish were significantly associated with the coastal group (odds ratio = 2.28; 95% confidence interval = 1.54 to 3.36). CONCLUSION Proximity to the shoreline may serve as an indicator for potential exposure in oil spills among vulnerable populations including children.

The goal of the study was to characterize risk pertaining to seafood consumption patterns following the Deepwater Horizon oil spill, among school children (K to 4th grade) residing in close proximity to the Gulf of Mexico in Mobile County, Alabama.Responses on seafood consumption pattern including the type of seafood and intake rate during the pre and post oil spill periods, from parents of 55 school children from three schools located20mile radius from the Gulf of Mexico shoreline (coastal group) were compared with those from parents of 55 children from three schools located ≥20miles away from the shoreline (inland group). We also estimated levels of concern (LOCs) in seafood for selected chemicals found in crude oil including heavy metals, and polycyclic aromatic hydrocarbons (PAH), and dioctyl sodium sulfosuccinate (DOSS), the primary compound in dispersants.The coastal group ate more seafood consisting primarily of crustaceans (62% vs. 42%, p=0.04) and fin fish (78% vs. 58%, p=0.02) from the Gulf of Mexico compared to the inland group, while the inland group ate more fin fish not found in the Gulf of Mexico (62% vs. 33%, p0.01). In the post-oil spill time period, both groups substantially reduced their consumption of sea food. On average, the coastal group ate ≥2 seafood meals per week, while the inland group ate ≤1 meal per week; these frequency patterns persisted in the post oil-spill period. Comparison of the estimated LOCs with contaminant levels detected in the seafood tested by the Food and Drug Administration and National Oceanic and Atmospheric Administration, post-oil spill, found that the levels of PAHs, arsenic, and DOSS in seafood were 1-2 orders of magnitude below the LOCs calculated in our study. Levels of methyl mercury (MeHg) in the seafood tested pre- and post- oil spill were higher than the estimated LOCs suggesting presence of higher levels of MeHg in seafood independent of the oil spill.In sum, the study found higher than average seafood consumption among children along the Mobile coastal area when compared to the inland children and the National Health and Nutrition Examination Survey (NHANES) estimates. Risk characterization based on the LOCs indicated no increase in risk of exposure despite higher seafood consumption rates among the study population compared to the general population.

Objective To evaluate 1943 to 2009 mortality among 22,785 synthetic rubber industry employees. Methods Standardized mortality ratio (SMR) and internal Cox regression analyses. Results Among hourly employees with more than or equal to 10 years worked and more than or equal to 20 years since hire, SMRs were elevated for leukemia (SMR = 139, 95% confidence interval [CI] = 106 to 179), non-Hodgkin lymphoma (NHL) (SMR = 136, CI = 102 to 177), bladder cancer (SMR = 148, CI = 110 to 195) and, for women only, lung cancer (SMR = 225, CI = 103 to 427). Butadiene and styrene exposure-response trends were positive for leukemia and bladder cancer but not for NHL or for lung cancer among women. Conclusions Results support a causal relationship between butadiene and leukemia. Interpretation of results for lung cancer among women and for bladder cancer is uncertain because of inability to control for smoking and inadequate or inconsistent support from other studies for an association between butadiene or styrene and the latter cancers.

Background and aimsThe Neonatal Behavior Assessment Scale (NBAS) was introduced by Brazelton is a useful tool to assess neurodevelopment in newborn in research setting. However, it is complex, time-consuming and requires specialized training for administration and is therefore difficult tool to use in routine clinical settings. The Alberta Infant Motor Scale (AIMS) is a simple tool to assess of motor maturation of a child up to 18 months and can be administered with minimal training for the health care professionals. The study goal of this study was to evaluate the reliability and validity of the AIMS in comparison with the NBAS in assessing motor maturity at birth.MethodsWe administered the AIMS and NBAS to a total of 66 newborn babies delivered in three obstetric units at the Colombo North Teaching Hospital in Ragama, Sri Lanka. The subjects were selected from a sample of 545 newborn babies in an ongoing birth-cohort study evaluating effects of prenatal exposure to biomass smoke and infant neurodevelopment. Trained research assistants administered first the NBAS, followed by the AIMS one-hour later. Univariate and bivariate statistics were used to compare the two scales.ResultsIrrespective of maturity, sex, birth weight or socio-demographic characteristics, all babies had scored on the 75th percentile in the AIMS. In the NBAS, there was a significant variation in the Brazelton motor score scaled to 100. Low birth weight babies showed a narrower variation in the NABS score. None of the scales indicated a motor deficit in any of the children.ConclusionNBAS identifies subtle differences in motor maturity of full term babies that the AIMS fails to detect

We updated the mortality experience of North American synthetic rubber industry workers to include follow-up from 1944 through 2009, adding 11 years of mortality data to previous investigations. The present analysis used Cox regression to examine the exposure-response relationship between 1,3-butadiene (BD) and styrene (STY) parts per million (ppm)-years and leukemia (N = 114 deaths), non-Hodgkin lymphoma (NHL) (N = 89) and multiple myeloma (MM) (N = 48). A pattern of largely monotonically increasing rate ratios across deciles of BD ppm-years and a positive, statistically significant exposure-response trend were observed for BD ppm-years and leukemia. Using continuous, untransformed BD ppm-years the regression coefficient (β) adjusted only for age was 2.6 × 10(-4) (p

Melioidosis is a severe and fatal infectious disease in the tropics and subtropics. It presents as a febrile illness with protean manifestation ranging from chronic localized infection to acute fulminant septicemia with dissemination of infection to multiple organs characterized by abscesses. Pneumonia is the most common clinical presentation. Because of the wide range of clinical presentations, physicians may often misdiagnose and mistreat the disease for tuberculosis, pneumonia or other pyogenic infections. The purpose of this paper is to present common pitfalls in diagnosis and provide optimal approaches to enable early diagnosis and prompt treatment of melioidosis. Melioidosis may occur beyond the boundaries of endemic areas. There is no pathognomonic feature specific to a diagnosis of melioidosis. In endemic areas, physicians need to expand the diagnostic work-up to include melioidosis when confronted with clinical scenarios of pyrexia of unknown origin, progressive pneumonia or sepsis. Radiological imaging is an integral part of the diagnostic workup. Knowledge of the modes of transmission and risk factors will add support in clinically suspected cases to initiate therapy. In situations of clinically highly probable or possible cases where laboratory bacteriological confirmation is not possible, applying evidence-based criteria and empirical treatment with antimicrobials is recommended. It is of prime importance that patients undergo the full course of antimicrobial therapy to avoid relapse and recurrence. Early diagnosis and appropriate management is crucial in reducing serious complications leading to high mortality, and in preventing recurrences of the disease. Thus, there is a crucial need for promoting awareness among physicians at all levels and for improved diagnostic microbiology services. Further, the need for making the disease notifiable and/or initiating melioidosis registries in endemic countries appears to be compelling.

Background: The Deepwater Horizon (DH) blowout resulted in fisheries closings across the Gulf of Mexico. Federal agencies, in collaboration with impacted Gulf states, developed a protocol to determine when it is safe to reopen fisheries based on sensory and chemical analyses of seafood. All federal waters have been reopened, yet concerns have been raised regarding the robustness of the protocol to identify all potential harmful exposures and protect the most sensitive populations. Objectives: We aimed to assess this protocol based on comparisons with previous oil spills, published testing results, and current knowledge regarding chemicals released during the DH oil spill. Methods: We performed a comprehensive review of relevant scientific journal articles and government documents concerning seafood contamination and oil spills and consulted with academic and government experts. Results: Protocols to evaluate seafood safety before reopening fisheries have relied on risk assessment of health impacts from polycyclic aromatic hydrocarbon (PAH) exposures, but metal contamination may also be a concern. Assumptions used to determine levels of concern (LOCs) after oil spills have not been consistent across risk assessments performed after oil spills. Chemical testing results after the DH oil spill suggest PAH levels are at or below levels reported after previous oil spills, and well below LOCs, even when more conservative parameters are used to estimate risk. Conclusions: We recommend use of a range of plausible risk parameters to set bounds around LOCs, comparisons of post-spill measurements with baseline levels, and the development and implementation of long-term monitoring strategies for metals as well as PAHs and dispersant components. In addition, the methods, results, and uncertainties associated with estimating seafood safety after oil spills should be communicated in a transparent and timely manner, and stakeholders should be actively involved in developing a long-term monitoring strategy.

Objective: To conduct an epidemiological and clinical review of published case reports of melioidosis from India and Bangladesh. Methods: Data from published case reports were abstracted and summarized. We further compared the clinical epidemiology of the melioidosis cases in India with case series from highly endemic areas in Northern Australia and Southeast Asia to elucidate any differences in presentations and risk factors between the regions. Results: We identified a total of 99 cases published between 1953 and June 2016, originating from India (n=85) or Bangladesh (n=14). Cases were predominantly male and ranged in age from 1 month to 90 years. Diabetes mellitus was the most common risk factor reported (58%). About 28% of the cases had history of exposure via high-risk occupations or exposure to contaminated water. The overall case fatality rate (CFR) was 26%. Factors influencing mortality included the occurrence of septic shock (CFR, 80%), environmental exposure (CFR, 39%), primary presentation of pneumonia (CFR, 38%), misdiagnosed and/or mistreated cases (CFR, 33%) or the presence of a risk factor (CFR, 29%). Because of the small number of cases in Bangladesh, pattern of clinical epidemiology is limited to India. Soft tissue abscess (37%) was the most common clinical presentation reported from India followed by pneumonia (24%) and osteomyelitis/septic arthritis (18%). Neurological melioidosis (n=10, 12%) presented as pyemic lesions of the brain or meninges. A few cases of prostatic abscess (n=4) in men and parotid abscess (n=4) were also noted. The above patterns were consistent with case series from Southeast Asia and Northern Australia for the most part, in terms of risk factors associated with infection and factors influencing mortality. Differences included clinical presentation of pneumonia which was notably lower than that reported in Southeast Asia and Northern Australia; a higher proportion of neurological and parotid abscess presentation; and a lower CFR compared to that reported in case series in Southeast Asia. About 39% of the cases were misdiagnosed and/or mistreated, suggesting underreporting and under estimation of the true disease burden. Conclusions: The concentration of melioidosis cases in southern and eastern states in India and in Bangladesh, which share climatic conditions and rice farming activities with known endemic areas in Southeast Asia, suggests an endemicity of melioidosis in this region. Thus, increased awareness among healthcare personnel, particularly among clinicians and nurses practicing in rural areas, and improved surveillance through case registries is essential to guide early diagnosis and prompt treatment.

Abnormalities in type I collagen have been recognized in a number of connective tissue disorders. In the Marfan syndrome, an autosomal dominant condition producing a generalized abnormality in connective tissue, no consistent abnormality has been identified, although one individual has been found to have an elongated pro alpha 2(I) collagen chain [Byers et al, Proc Natl Acad Sci USA 78:7745, 1981]. To determine the nature of the alteration in the gene that produced this abnormality, we studied the pro alpha 2(I) gene from this individual by genomic blotting and gene cloning. Genomic mapping studies detected no abnormalities. However, analysis of the cloned segment of the pro alpha 2(I) collagen gene from the Marfan individual indicates that the gene contains a 38 base pair insertion in an intron near the collagenase cleavage site. Although the relationship of this insertion to the protein abnormality is unclear, it may be a useful marker for the diagnosis of the Marfan syndrome.