A study on the interdependence of heavy metals while contributing to groundwater pollution index.

The contribution of heavy metal to the groundwater pollution index (m-HPI) is dependent on other heavy metals present in it. This contribution may be synergistic or anti-synergistic (antagonistic) depending upon the constituent matrix. Both heavy metal type and its concentration are important. m-HPI, a variant of heavy metal pollution index in water, may be calibrated against USEPA hazard index (HI) using a generic multivariate non-linear regression (MVNLR) model. Excellent correlation may be obtained between HI and m-HPI through optimization of normalized weightage factors of constituent metals that contribute to m-HPI. MVNLR model was employed on groundwater samples of ten sites having different heavy metal matrix. The synergistic/antagonistic contribution of heavy metals to m-HPI was well discernible at each site. This study clearly showed that the individual contribution of a particular heavy metal to pollution index might be altered (enhanced or reduced) in the presence of other heavy metals. A calibrated MVNLR model was successfully used for predicting the hazard index (HI) of water samples.

Risk stratification for malignant progression in Barrett's esophagus: Gender, age, duration and year of surveillance.

AIM: To clarify risk based upon segment length, diagnostic histological findings, patient age and year of surveillance, duration of surveillance and gender. METHODS: Patients registered with the United Kingdom Barrett's Oesophagus Registry from 9 United Kingdom centers were included. The outcome measures were (1) development of all grades of dysplasia; (2) development of high-grade of dysplasia or adenocarcinoma; and (3) development of adenocarcinoma. Prevalent cases and subjects with < 1 year of follow-up were excluded. The covariates examined were segment length, previous biopsy findings, age at surveillance, duration of surveillance, year of surveillance and gender. RESULTS: One thousand and one hundred thirty six patients were included (total 6474 patient-years). Fifty-four patients developed adenocarcinoma (0.83% per annum), 70 developed high-grade dysplasia/adenocarcinoma (1.1% per annum) and 190 developed any grade of dysplasia (3.5% per annum). High grade dysplasia and adenocarcinoma increased with age and duration of surveillance. The risk of low-grade dysplasia development was not dependent on age at surveillance. Segment length and previous biopsy findings were also significant factors for development of dysplasia and adenocarcinoma. CONCLUSION: The risk of development of low-grade dysplasia is independent of age at surveillance, but high-grade dysplasia and adenocarcinoma were more commonly found at older age. Segment length and previous biopsy findings are also markers of risk. This study did not demonstrate stabilisation of the metaplastic segment with prolonged surveillance.

The socioeconomic profile of a Barrett's oesophagus cohort assessed by the 2010 Index of Multiple Deprivation.

BACKGROUND: Several reports have described the relationship between socioeconomic status and oesophageal adenocarcinoma but only one with its precursor condition, Barrett's oesophagus. We therefore investigated such an association. PATIENTS: The majority (88%) of patients diagnosed with Barrett's at Rotherham District General Hospital between 28 April 1978 and 31 August 2012 consented to inclusion in the UK Barrett's Oesophagus Registry. Those residing within Rotherham form the basis of this study. METHODS: We assessed socioeconomic status using the Index of Multiple Deprivation 2010 scores which can be assigned to every English postcode. The scores for the whole of England were divided into five equal groups; those of the 6257 postcodes within Rotherham (including those of Barrett's patients) were compared against the national quintile relevant to their score. We examined the ratio of observed against expected numbers of Barrett's in each quintile before and since 2001, the median year of diagnosis. RESULTS: The study group comprised 1076 patients with Barrett's oesophagus. Before 2001 their distribution across the deprivation quintiles was similar to that expected. Since then it has changed significantly, with 37% more Barrett's patients than expected among the two least deprived quintiles, but 11% fewer than expected in the larger population comprising the two most deprived quintiles (P=0.0001). There was no significant difference in the distribution of sex (P=0.27), nor the mean age at diagnosis between the two time periods (P=0.92). CONCLUSION: Since 2001, there has been a major change in the distribution of Barrett's in relation to socioeconomic status, measured by the Index of Multiple Deprivation.