Melanie Stewart


My honours research aims to investigate the effects of environmental endocrine disruptors (EEDs) on mouse reproduction. EEDs are compounds that can interfere with natural hormonal signaling in animals. They may be synthetic, such as those found in plastics, pesticides, or drugs, or natural such as genistein, a major component of soy. EEDs have been linked to the recent increase in incidence of disorders of sexual development (DSDs), such as hypospadias.  Of particular interest to me are EEDs that mimic oestrogen signaling, termed oestrogen agonists. As there is a conserved role for oestrogen in vertebrate sex determination, EEDs can affect many animals including fish, amphibians, marsupials and eutherians. Exposure to such chemicals in utero can alter sexual development, and therefore have long-term impacts on that individual’s fitness. Through my research, I aim to characterise the effects of the endocrine disruptor diethylstilbestrol on mouse gonadal and genital tubercle development. In the future, I hope to use this as a basis for investigating other EEDs in a broad range of mammals. I am also interested in the potential effects EED exposure has on subsequent generations through epigenetic modification. Overall, these findings could assist human health and conservation efforts.