This tool is being developed to enable people to test sources of water for the presence of environmental estrogens. An increasing number of structurally diverse chemicals encountered in the environment and common household items have been identified as environmental estrogens, compounds that can mimic many of the effects of natural estrogens. Well-studied examples include DDT and several other pesticides, chemicals such as BPA and nonylphenol that leach from polycarbonate and certain other plastics, and some flame retardants. Pharmaceutical estrogens used for birth control and hormone replacement therapy in humans, as well as hormones used in commercial animal feedlot operations, end up in wastewater effluents that discharge to surface waters. Once studied and discussed mainly by specialists in academic labs and regulatory agencies, the past several years have seen an enormous increase in public awareness and interest in the sources, routes of exposure, and potential impacts of environmental estrogens on human health and biodiversity. There is growing concern that developmental exposures to such chemicals may have significant adverse effects on human health particularly in light of the ubiquity of exposure to environmental estrogens. Wildlife is also susceptible to environmental estrogens through exposures to pesticide runoffs from farmlands, excretion of synthetic estrogens by humans and farm animals, and estrogenic surfactant by-products of many compounds used in manufacturing. It is believed that environmental estrogens are contributing to the large rise in the numbers of feminized fish seen in this country and elsewhere and may be a factor in biodiversity losses worldwide. Because of the magnitude of concern over potential impacts of environmental estrogens, and the lack of basic information about possible estrogenic activities of most of the 80,000+ chemicals registered for use, there have been mounting efforts to develop simple laboratory assays for estrogenic activities of individual chemicals, environmental water samples, and chemicals that migrate from consumer products such as water bottles, baby bottles, food containers, children’s toys and plastic-based resins. One of the simplest of these is the yeast-based YESassay, in which a standard lab yeast strain has been engineered to contain (i) a human ER (hER) and (ii) a gene that, when bound by activated hER, produces the enzyme β-galactocidase (β-gal). In the absence of estrogen, no β-gal is produced. When estrogen or an estrogenic chemical like BPA is added, it induces synthesis of β-gal, which is then detected by a simple colorimetric assay in which β-gal converts one chemical (yellow) into a modified form (red), a reaction that is readily detected by simple visual inspection. While more sensitive and complex yeast-based assays have since been developed, those demand more expensive chemicals and instrumentation. As described in more detail later, the original YESassay is simple, robust and inexpensive enough to make it feasible as an assay for community-based education and testing. Thus, we plan to develop materials and protocols for this assay in a version that is suitable for community-based testing for environmental estrogens.
Applications and example uses
We're using it here .... for detecting...
It looks like this... (photos)
How to make your own
- image (of the inside, or the kit laid out on the ground, a "sum up" image, best if labelled)
- list of parts
- time to build? "2 hours" or "30 mins"
- prerequisites -- you'll need a screwdriver, or the GlowDoodle software
If this is too long, link to another page...
How to use it
- basic usage in text
- links to illustrated guides
- a YouTube video or several?
If this is too long, link to another page...
- List next steps
- short-term goals
- and places to start contributing
If need be, link to the mailing list so people know where to go to get in touch.
This is a research project that the Public Lab Toxics and Health working group is kicking off over the next couple of months. We are collaborating with Joan Ruderman from Harvard University and Gary Wessel from Brown University. Research on the project is sited at a lab at Brown. We would love to have any public laboratory people help us out in this research process, email the public lab list if you're interested in joining in!
[[http://publiclaboratory.org/tool/home-testing-endocrine-disruptors|Home Testing for Endocrine Disruptors]]
We are currently doing background readings on the human and environmental health impacts of environmental estrogens. Here is our reading list so far.
Excellent Place to Start in learning about this issue: http://e.hormone.tulane.edu/learning/estrogens.html
General literature on well characterized common environmental estrogens:
We are attempting to develop a testing kit for environmental estrogens using yeast that contain the human estrogen receptor as described in this paper.
List the bibliography.
Draw a diagram how the YES assay works.
Contributors: Avery Louie at Olin College RISD Yuyu and Mara Sara Wylie
To Do List before January 23rd grow week!
- read up on growing yeast--particularly home brewing kits
- read up on how to prepare water samples for testing. --Bisphenol A samples from water bottle --water from tap --water with Phthalates --what other samples could we test?
- develop concepts for designing home testing kits
- develop concept for gallery show
Link to related posts (Mara tag earlier post) [[http://publiclaboratory.org/wiki/hometesting-environmental-estrogens-bibliography|Bibliography for Estrogen Screen project]]
[[http://publiclaboratory.org/notes/mara/10-27-2011/possible-estrogen-culture-vessels|possible vessel for estrogen cultures]]