Another update on our currently running module “Living with Environmental Change” and another host of excellent guest speakers. At St. Lukes, we had the pleasure to hear Dr. Fiona Mathews talk about “The Environment and Reproductive Health”. Fiona has done some amazing work on reproductive biology, a topic of fundamental interest to evolutionary biologists (see here for example). She presented a range of her findings, including the observation that there are statistically more male than female still births, a pattern consisten across the world in countries with varying levels of income, which is not yet understood. Another topic was the detrimental effect of mobile phone usage on sperm quality and yet another amazing finding (that made headlines all over the world) is that maternal diet at conception influences the chance of having a boy or a girl. This is such a cool graph that I have bothered to copy the legend (read the paper here).

Relationship between usual maternal intakes of energy and breakfast cereal prior to pregnancy, split at approximate tertiles, and the proportion of male infants (Cs.e.m.). Comparisons of the numbers of males and females across the groups were made using c2-test for linear association. The numbers above each bar indicate the numbers of women in each category of intake. For energy, the bars represent the low (open), moderate (filled) and high (hatched) thirds of intake; c2Z5.83, pZ0.016. For breakfast cereal, the bars represent less than one bowl per week (open), two to six bowls per week (filled) and one or more bowl per day (hatched); Chi sq.=13.96, p<0.001.
At Penryn, we had a very different, but equally interesting and relevant lecture that week, namely by Professor Steve Rowland, who is at Plymouth University, but also has an honorary professorship at Exeter. Steve talked about his research on the environmental impacts of oil contamination, in particular about the tar sands in Canada. This politically controversial topic was all over the news that week because of the elections in Canada and because of Shell’s decision to shut down its operations there for the foreseeable future, again demonstrating how topical the module is. The extraction of oil from tar sands is an absolutely massive operation (tailings ponds can be seen from space) with far-ranging impacts on the environment and human populations. I really liked the format of this lecture, which consisted of a multiple choice question, followed by student discussion after which more in-depth explanation was given. Another session was delivered by Professor Tamara Galloway in Penryn and Professor Lorna Harries in Exeter; both spoke about their joint work on Bisphenol A (BPA). BPA is the world’s highest production volume compound with 3.2 million tonnes produced per year (earning producers £500k per hour). Originally developed as a synthetic oestrogen, it was later discovered that this molecule was great for the production of polycarbonate plastics, ubiquitously present in consumer goods. However, the problem is that BPA slowly leaches out of plastic packaging (especially when microwaved), thermal receipts and the lining of tin cans. BPA can be detected in urine in about 93% of us and there are statistically significant associations of BPA levels in humans with adverse effects on health, see for instance here:
The lecture highlighted some of the ongoing work by Galloway and Harries, including a study where school children follow a diet minimizing the use of packaged (junk)food, followed by the monitoring of BPA levels in urine and gene expression of two genes where expression has been shown to vary with BPA levels. Very interesting stuff that of course led up to discussions on how to limit BPA levels in our own daily lives. More Living with Environmental Change module updates to follow!
Michiel