Some chemicals implicated so far
This page outlines some of the chemicals
which have been implicated as hormone disrupters. In most cases,
I have written a more detailed page (or pages) on the chemical.
Note that due to the large quantity of research now being published,
and the plethora of chemicals implicated in some way, it is not
possible for me to list every chemicals. In addition, it is not
always possible to keep all the specific chemical pages totally
up to date.
The chemicals are divided into three groups,
'Industrial Chemicals' , 'Natural Hormones',
and on a separate page, 'Pesticides'.
Industrial Chemicals
This group of chemicals are very widely
used as plasticisers in plastics such as PVC, but some of them
are also testicular toxins and can disrupt hormones. More
details.
Alkylphenols and their derivatives have
a variety of uses, including as industrial detergents and, outside
Europe, as domestic detergents . They have been shown to be oestrogenic
in many systems. More details.
An ingredient of lacquers that are used
in dental treatment, and to coat metal containers such as food
cans. It has been shown to leach from these cans into vegetables,
and it is oestrogenic to human breast cancer cell cultures. More details.
Dioxins are often produced during incineration,
and also by some industrial processes, such as the production
of chlorinated hydrocarbons and paper production. PCBs were used
in electrical equipment such as transformers, but were banned
some years ago. However, a large quantity of PCBs is still present
in transformers and capacitors. More details.
Brominated flame retardants are a group
of chemicals that are used in plastics and textiles to give flame
retardant properties. Many of them are persistent and bioaccumulative,
and several are hormone disrupters. More details.
A group of chemicals used as preservatives
in cosmetics, and in some antibacterial toothpastes. Several
chemicals in the group are oestrogen mimics. More
details.
Butylated hydroxyanisole
Butylated hydroxyanisole (BHA) is a food
antioxidant. It is slightly oestrogenic to breast cancer cells,
binds rainbow trout oestrogen receptor and stimulates transcriptional
activity of the human oestrogen receptor (Jobling et al., 1995).
Natural Hormones
Phytoestrogens are natural hormones present
in many plants, and in particularly high levels in soya. More details.
Pollution by female hormones
Research in the UK has found that sewage
effluents, and in some cases rivers, were oestrogenic, causing
the production of vitellogenin (egg yolk protein) in male trout.
Further research and fractionation of sewage effluents led to
the identification of oestrone and 17beta-oestradiol as the main
source of oestrogenic activity in most effluents (EA, 1997).
These two hormones are naturally excreted, in a conjugated form,
in the urine of women; bacteria in the sewage works then re-activate
the hormones (Panter et al., 1999). The fractionation research
also detected ethinyl oestradiol, from the contraceptive pill,
in some effluents, but the natural oestrogens were always more
important.
Note that sewage effluents do also contain
other oestrogens, in particular alkylphenols
(though not in UK domestic effluents), but also others.
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