Exposure to polychlorinated biphenyl (PCB) congeners measured shortly after giving birth and subsequent risk of maternal breast cancer before age 50

Discrete windows of susceptibility to toxicants have been identified for the breast, including in utero, puberty, pregnancy, and postpartum. We tested the hypothesis that polychlorinated biphenyls (PCBs) measured during the early postpartum predict increased risk of maternal breast cancer diagnosed before age 50. We analyzed archived early postpartum serum samples collected from 1959 to 1967, an average of 17 years before diagnosis (mean diagnosis age 43 years) for 16 PCB congeners in a nested case–control study in the Child Health and Development Studies cohort (N = 112 cases matched to controls on birth year). We used conditional logistic regression to adjust for lipids, race, year, lactation, and body mass. We observed strong breast cancer associations with three congeners. PCB 167 was associated with a lower risk (odds ratio (OR), 75th vs. 25th percentile = 0.2, 95 % confidence interval (95 % CI) 0.1, 0.8) as was PCB 187 (OR, 75th vs. 25th percentile = 0.4, 95 % CI 0.1, 1.1). In contrast, PCB 203 was associated with a sixfold increased risk (OR, 75th vs. 25th percentile = 6.3, 95 % CI 1.9, 21.7). The net association of PCB exposure, estimated by a post-hoc score, was nearly a threefold increase in risk (OR, 75th vs. 25th percentile = 2.8, 95 % CI 1.1, 7.1) among women with a higher proportion of PCB 203 in relation to the sum of PCBs 167 and 187. Postpartum PCB exposure likely also represents pregnancy exposure, and may predict increased risk for early breast cancer depending on the mixture that represents internal dose. It remains unclear whether individual differences in exposure, response to exposure, or both explain risk patterns observed

Introduction and timetable

The problem of environmental assessment, which is addressed in this module, is much more about bringing together a very wide range of skills and approaches than investigating in depth from a single point of view. We have therefore adopted an empirical approach where you, the student, will start from a real problem and, under the supervision of a course team with a range of skills, will assemble a viable and holistic approach to its solution. [fragm. tekstu

The lecture programme

Environmental management can be viewed as a complete spectrum along which society first identifies an issue or pro-blem, and subsequently assesses its importance, develops possible solutions, implements actions, then monitors (and evaluates) the effectiveness of the actions. There are different “players” or “actors” at each stage, e.g. the government or local authorities, nongovernmental organisations (NGOs), environmental consultants, scientists, individuals, etc. At each stage different actors can have an input into a particular process of varying significance, depending on the issue or problem identified. [fragm. tekstu

Anthropogenic disturbance as a factor supporting the development of rare species as exemplified by Botrychium matricariifolium in the Silesia region of Poland : [poster]

Botrychium matricariifolium (Retz) A. Braun ex W.D. J. Koch (daisy-leaved moonwort; Ophioglossaceae), an endangered and strictly protected species ofmoonwort has lost significant number of its localitiesduring recent decades in Poland. From over 200 knownlocalities from the area of the entire country, only aboutthirty were confirmed in the period of last 30 years. Themajority of known populations usually consists of a fewindividuals or even a single individual plant. Little isknown about the life history of the species, and what ismore, until now no monitoring of the existing populations has taken place (Fragment tekstu)