In utero exposure to low doses of environmental pollutants disrupts fetal ovarian development in sheep

Epidemiological studies of the impact of environmental chemicals on reproductive health demonstrate consequences of exposure but establishing causative links requires animal models using ‘real life’ in utero exposures. We aimed to determine whether prolonged, low-dose, exposure of pregnant sheep to a mixture of environmental chemicals affects fetal ovarian development. Exposure of treated ewes (n = 7) to pollutants was maximized by surface application of processed sewage sludge to pasture. Control ewes (n = 10) were reared on pasture treated with inorganic fertilizer. Ovaries and blood were collected from fetuses (n = 15 control and n = 8 treated) on Day 110 of gestation for investigation of fetal endocrinology, ovarian follicle/oocyte numbers and ovarian proteome. Treated fetuses were 14% lighter than controls but fetal ovary weights were unchanged. Prolactin (48% lower) was the only measured hormone significantly affected by treatment. Treatment reduced numbers of growth differentiation factor (GDF9) and induced myeloid leukaemia cell differentiation protein (MCL1) positive oocytes by 25–26% and increased pro-apoptotic BAX by 65% and 42% of protein spots in the treated ovarian proteome were differently expressed compared with controls. Nineteen spots were identified and included proteins involved in gene expression/transcription, protein synthesis, phosphorylation and receptor activity. Fetal exposure to environmental chemicals, via the mother, significantly perturbs fetal ovarian development. If such effects are replicated in humans, premature menopause could be an outcome

A case study investigating the occurrence of geosmin and 2-methylisoborneol (MIB) in the surface waters of the Hinze Dam, Gold Coast, Australia

The Hinze Dam is located in the Gold Coast Hinterland and is the primary source of water supply for the Gold Coast region. Sporadic and unpredictable taste and odour events caused by Geosmin and 2-methylisoborneol (MIB) are an ongoing problem in the Hinze Dam. To investigate potential ecological and physiological triggers of these events, a 12-month surface-sampling regime was undertaken. Concentrations of geosmin, MIB, nitrogen, and phosphorus were measured. Algal and cyanobacterial counts were performed. Water temperature, rainfall and dam capacity were also recorded. The occurrence of geosmin was found to correlate significantly with Anabaena numbers, water temperature and dam capacity. The occurrence of MIB correlated with increasing ammonia. No significant correlations were observed with the other nutrients or physical parameters measured. Overall, this study demonstrated that high concentrations of geosmin detected in dam surface waters was strongly correlated with an increase in numbers of Anabaena sp.. These events were most likely triggered by significant rainfall causing a pulse in nutrients into the dam, in conjunction with warmer water temperatures.Griffith Sciences, School of Natural SciencesNo Full Tex

Early-Late Cretaceous (Aptian-Cenomanian) Palynomorphs

Abstract. Samples from 12 wells situated mainly in the northern part of the Cyrenaica Shelf of northeast Libya have yielded palynomorph assemblages of Aptian, Albian or Cenomanian aspect. The Aptian assemblages are dominated by land-plant remains and contain relatively few dinoflagellate cysts. By contrast, the latter are generally common in those from the Albian and Cenomanian samples. Deposition in near-shore marine environments is indicated for most of the Aptian succession whereas more open marine conditions are generally suggested for the younger strata. In places, however, a substantial terrestrial input was maintained during the accumulation of the Albian sediments.Dinoflagellate cysts typically recorded from Aptian palynological preparations include Aptea anaphrissa, Cyclonephelium sp. 1, Hystrichosphaerina schindewolfii, Muderongia simplex microperforata and Occisucysta spp. Several species of Cribroperidinium, but especially C. edwardsii and C. orthoceras, usually form an important part of the Albian assemblages; Kiokansium hydra is also often present. Skolochorate cysts referable to Coronifera and Florentinia are abundant in both these and the Cenomanian preparations, with Palaeohystrichophora infusorioides and several species of Canningia, Cyclonephelium, Oligosphaeridium, Spiniferites and Subtilisphaera being among the most numerous of the associated forms. In general the assemblages compare closely with those of similar age described by Below (1981, 1982) and Williams (1978) from onshore and offshore Morocco respectively.Although miospores are common in the Aptian preparations, they show relatively little morphological diversity. Smooth walled triradiate specimens, Classopollis and Inaperturopollenites are often the dominant forms. Angiosperm pollen grains are generally scarce and bisaccates only rarely encountered. A few of the Albian . . . </jats:p