The U.S. Food and Drug Administration (FDA) announced a total ban on the sale of antibacterial soap in early September 2016 because there is no evidence that antibacterial soap is more hygienic and safe than regular soap.
In recent years, some bathing agents, detergents are deeply involved in the problem of "environmental hormones", when they enter the human body, the endocrine system mistakes it for natural hormones, absorbs and utilizes them, occupies the position of normal hormones in human cells, thereby triggering endocrine disorders, causing abnormal metabolism of normal hormones in the human body, bringing potential threats to human health.
So, what exactly are "environmental hormones"? What are the means and methods of detecting environmental hormones?
Demystify environmental hormones
Environmental hormones, also known as environmental hormones, refer to exogenous chemicals that interfere with the normal endocrine function of animals and humans. Environmental hormones are widely present in environmental media such as atmosphere, water and soil, and can be released into the marine environment in large quantities through atmospheric sedimentation, surface runoff, oil spills and pollution emissions. Environmental hormones are difficult to degrade and interact and distribute with water, suspended particulate matter, aquatic organisms and sediments when they enter the ocean.
Types of environmental hormones: Environmental hormones can generally be divided into 13 categories according to their use, as shown in Table 1.
Table 1 Types of environmental hormones
type
name
detergent
C5~C9 alkylphenol, nonylphenol, 4-octylphenol, triclosan, trichlorocarban
germicide
HCB), Daisen manganese, Daisen manganese zinc, Daisen Lian, Daisen zinc, ethylene sclerotia, Fumei zinc, Fumei bis, benomylin, alenosterone, humus, carbendazim, imidaamide, isobacterium urea, triazolone, triazolol, thizolin, earth mycopramine
preservative
Pentachlorophenol (PCP), tributyltin (TBT), triphenyltin (TPT)
herbicide
2,4,5-Trichlorophenoxyacetic acid, 2,4-dichlorophenoxyacetic acid, herbicide, fluorodescen, methylchloramine, acetochloramine, herbicide ether, chlorphenoxygine, sycoazine, cimacin, flulodrone, ricolon, amchloropyridine, tertin, dichloropyridine, dichloropyridine, bromobenzonitrile, chlorphenirone
insecticide
Hexa-66, parathion, methenaphthrine, chlordane, ultra-nine chlorine, DDD, DDT, DDE, trichlorocarbicides, di reagent, endemicrin, heptane, heptachlor, epoxy heptachlor, malathion, methoxy dread, fendovir, 1,2-dibromo-3-chloropropane, 16O5, tranhtha naphthalene, aldrin, octachlorne, kaipeng, cypermethrin, cypermethrin, permethrin, mirex, methoxychloride, olamine, permethrin, borax thiophosphate, bifenthrin, cypermethrin, cypermethrin, methenavir, rafflein, Diazinphos, Leguo, Acetylmethaphos, Dioptera
Plastic plasticizers and various plastic products
Dihexyl phthalate (DEHP), benzyl phthalate (BBP), dibutyl phthalate (DBP), biscyclohexyl phthalate (DCHP), bis diethyl phthalate (DEP), dicaprylyl adipate, bis-2-ethylhexyl adipate, dipropyl phthalate, bis-2-ethylhexyl phthalate, bis(b) abiphosphate, bisphenol A, styrene, polychlorinated biphenyls (PCBs), polybrominated biphenyls (PBBs), vinyl chloride
Fragrance
4-Ethylphenol, benzophenone (blybenzophenone)
dye
Alkylphenol, 4-(nitro)toluene, 2-naphthol, 2,4-dichlorophenol, amidazole, 3-amino-1,2,4-triazole
paints
Tributyltin, triphenyltin
Cosmetic materials
Benzophenone, anti-acid agent BHA, hydroxybenzene, phthalates
byproduct
Dioxins, furans, benzo[a]pyrene, octachryl styrene, p-nitrotoluene, styrene bis(or tri)polymer
Medical drugs
Hexenstildiol (DES), phthalimide piperidine (hypnotic), contraceptive
heavy metal
Cadmium and its compounds, lead and its compounds, mercury and its compounds
In addition to this, there are currently many chemicals that need to be further confirmed whether they have hormonal effects, and as research continues to deepen, some new environmental hormones will be confirmed.
Characteristics of environmental hormones
Most of the environmental hormone substances are fat-soluble compounds, with stable chemical properties, long metabolic half-life, chronic toxicity key hazard characterization properties, and strong biological enrichment. Even if the concentration in the environment is very low, it can accumulate in biological cells, and gradually pass along the food chain for enrichment, and finally enter the human and higher animals at a very high concentration, accumulating in tissues such as brains and gonads.
Detection method
Original Contest Entries: Guardians of Water
In view of the many hazards of environmental hormones, such as reproductive abnormalities, animal feminization, carcinogenic teratogenicity. The above content is a brief introduction to environmental hormones, which are the preliminary research data of this project. So how to monitor and then supervise such substances has become a difficult problem in front of us.
Below I will elaborate on the detection of environmental hormones in combination with the analytical means of this laboratory.
1 Means of pre-concentration
The current pre-concentration methods are mainly Based on Sowell extraction and liquid-liquid extraction, of course, there are also solid phase extractions, but these are generally used in instrumental analysis. When bioanalysis is used, the results can be greatly biased due to the toxic effect of the extractant on the subject organism.
2 Detection methods
From the general category, the current detection methods of environmental hormones can be divided into two categories: instrumental method and biological method, which complement each other and have their own advantages.
2.1 Instrumentation Method
Instrumental method is the traditional method of environmental hormone testing, which is detected according to its physical and chemical characteristics such as molecular size, mass, and charge. With the continuous improvement of instrument detection technology, there are more and more detection methods of environmental hormones, including ICP, HPLC-FL, LC-MS, GC-MS, GC-ECD-MS and so on.
Overall, these instruments can test almost all 70 substances in the table. Except for the three known heavy metals with environmental hormonal effects that are analyzed using ICP, the rest of the substances are basically separated by gas phase or (high performance) liquid phase, and then accurately quantified by ECD, MS, FL and other detectors according to the characteristics of the substance. Relatively specific and precise analysis is the advantage of the instrumental method, but also the disadvantage of the method. Especially for larger molecules, because LC cannot make a spectral library, it is difficult to qualitatively quantify without a standard control, so it is difficult to analyze unknown substances.
At the same time, the accuracy of the instrumental method refers to the accuracy of the classification and quantification of substances, but the test results do not provide information about the comprehensive effect (or toxicity) of environmental hormones on living organisms.
PS: The organic matter of small molecules of 67 kinds of organic substances that have been confirmed is separated by GC, and the large molecules are separated by LC
2.2 Biological Law
In view of the various defects of the instrumental method, the biological law has its existential significance. Although its quantitative accuracy is not as accurate as the instrumental method, and the precision of the test results is relatively low (possibly due to the difference in the subject material), many biological methods can give guidance on the effects of environmental hormones on the organism, which is of great significance for assessing the hazards of compounds or test samples (what we are most concerned about should not be how much concentration of a substance is, but whether it has an impact on us. If there is no impact, high and low can also be left alone).
At present, the commonly used biological methods for testing environmental hormones include morphological detection, yolkinogen (VTG) detection, enzyme-linked immunoassay, recombinant gene yeast method, uterine weight gain test, receptor competition test, endogenous gene expression method, etc. Here are a few of the more common and relatively simple methods, as well as common devices for testing environmental hormones using biological methods.
2.2.1 Morphological testing
The most commonly used morphological test is the Japanese medaka. Medaka has a companion body color gene r, using its alleles to produce a system to distinguish males and females by body color differences, and can distinguish genetic males and females by body color. Therefore, the estrobial ratio can be easily analyzed through a low-dose embryo infection test, and it is possible to determine whether the subject sample has an estrogen effect. This method is the most economical, and if you cultivate standard fish fingerlings yourself, the experiment will not cost much money.
2.2.2 Oviroteinogen (VTG) test
The yolk protein progen (VTG) detection method is currently one of the more used methods, and there are many kinds of kits for crucian carp, carp, butterfly chrysalis golden wasp, crayfish yolk proteinogen and so on. Since ELISA can only detect the content of immunoreactive cytokine proteins, which do not fully represent the level of biological activity of cytokines, there are also certain defects. In addition, the current price of these kits is still high, and the cost of batch testing is higher if the finished product is purchased.
2.2.3 EROD enzyme-linked immunoassay
The figure above is the schematic diagram of the EROD enzyme-linked immunoassay, which in my memory is measured of dioxins, and the material used is murine liver cancer cells. However, it seems that this cell is not very well cultured. The last time I did it at the Ecology Center of the Chinese Academy of Sciences, it didn't seem to be cultivated to the best. Overall, the experimental material is not expensive, but this experiment is not easy to do; and the test is dioxins, the most toxic of environmental hormones, not the overall effect of environmental hormones.
2.2.4 Recombinant gene yeast method
The recombinant gene yeast method is a bit expensive. I have had several inexplicable false negatives during the test, and I have not fully confirmed the cause. Analyze the masters together.
3 Summary and Outlook
Instrumental and biological methods complement each other for the analysis and testing of environmental hormones, biological methods are suitable for characterizing whether the sample is contaminated with environmental hormones, and can give information on the biological impact of the sample. The instrument law is suitable for identifying the types of environmental hormones under the premise of environmental hormone pollution given by biological method, determining the main pollutants, and then analyzing the source of pollution.
In view of the high detection limit of biological method test results and the fact that many pretreatment methods are not fully applicable, it is purely personal to use organisms to enrich and concentrate samples (I don't know if it is feasible or not, purely personal opinion).
Xiao Yi is sorted out.
Click to read the original article to view the relevant testing topics
↓↓↓