epoxy resin
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Rehabilitation of aged drinking water pipes is an extensive renovation and increasingly topical in many European cities. Spray-on-lining of drinking water pipes is an alternative cost-effective rehabilitation technology in which the insides of pipes are relined with organic polymer. A commonly used polymer is epoxy resin consisting of monomer bisphenol A (BPA). Leaching of BPA from epoxy lining to drinking water has been a concern among public and authorities. Currently epoxy lining is not recommended in some countries. BPA leaching has been demonstrated in laboratory studies but the behavior and ageing process of epoxy lining in situ is not well known. In this study 6 locations with different age epoxy linings of drinking water pipes done using two distinct technologies were studied. While bisphenol F, 4-n-nonylphenol, and 4-t-octylphenol were rarely found and in trace concentrations, BPA was detected in majority of samples. Pipes lined with the older technology (LSE) leached more BPA than those with more recent technology (DonPro): maxima in cold water were 0.25 μg/L and 10 ng/L, respectively. Incubation of water in pipes 8-10 h prior to sampling increased BPA concentration in cold water 1.1-43-fold. Hot water temperature caused even more BPA leaching - at maximum 23.5 μg/L. The influence of ageing of epoxy lining on BPA leaching on could be shown in case of LSE technology: locations with 8-9 years old lining leached 4-20-fold more BPA compared to a location with 2-year-old lining. Analysis of metals showed that epoxy lining can reduce especially iron concentration in water. No significant burden to water could be shown by the analyzed 72 volatile organic compounds, including epichlorhydrin, precursor used in epoxy resin. Estrogenicity was detected in water samples with the highest BPA loads. Comparable responses of two yeast bioreporters (estrogen receptor α and BPA-targeted) indicated that bisphenol-like compounds were the main cause of estrogenicity. Compared to the estimated average daily BPA exposure, additional BPA load via cold drinking water in the studied locations was low, maximum 8.7%. However, hot water should also be considered as exposure source due to higher BPA concentrations. Epoxy lined locations should be monitored in future in order to evaluate ageing process and control increasing leaching of potentially harmful chemicals.
- MeSH
- benzhydrylové sloučeniny MeSH
- chemické látky znečišťující vodu MeSH
- epoxidové pryskyřice * MeSH
- fenoly chemie MeSH
- lidé MeSH
- pitná voda chemie MeSH
- velkoměsta MeSH
- znečištění vody MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- velkoměsta MeSH
Přecitlivělost na epoxidové pryskyřice je běžnou příčinou kontaktní alergické dermatitidy, velmi často dochází k senzibilizaci při práci s nevytvrzenými pryskyřicemi. Vytvrzené pryskyřice ztrácejí iritační i senzibilizační potenciál. Kontaktní alergie se může vyvinout na epoxidy, ale i na tvrdidla a další látky epoxidových systémů. Nejčastěji postiženými profesemi jsou lakýrníci, podlaháři a dělníci v elektrotechnice. Je uveden typický případ profesionální kontaktní alergické dermatitidy na epoxidové pryskyřice u pacienta, který pracoval jako lakýrník. Při práci používal barvy na bázi epoxidů. V klinickém obraze dominovaly ekzémové projevy na obličeji a na předloktích. Epikutánními testy byla prokázaná kontaktní přecitlivělost na epoxidovou pryskyřici – bisfenol A, který je obsažen v Evropské standardní sadě epikutánních testů. Po vyřazení z kontaktu s epoxidy došlo k postupnému odhojení projevů kontaktní alergické dermatitidy.
Sensitivity to epoxy resins is a common cause of allergic contact dermatitis which often occurs during work with uncured epoxies. Hardened epoxy resins loose their irritant and allergic potential. Contact allergy may appear to epoxy resins, hardeners and other substances of epoxy systems. The most affected professions are lacquerers, floor workers and workers in electronic industry. A typical case of professional contact dermatitis to epoxy resins in pacient who worked as lacquerer with epoxy paints is reported. The patient presented with eczema eczema on the face and on the forearms. The contact allergy to epoxy – resin Bisphenol A which is included in European Standard Series of Patch Test Allergens, was proved by patch testing. After elimination of contact with epoxy resins the contact allergy symptoms gradually disappeared.
- Klíčová slova
- kontaktní alergická dermatitida – epoxidové pryskyřice – profesionální expozice,
- MeSH
- alergická kontaktní dermatitida * diagnóza etiologie MeSH
- bisfenol A-glycidyl methakrylát chemie škodlivé účinky MeSH
- dermatitida z povolání diagnóza etiologie MeSH
- dospělí MeSH
- epoxidové pryskyřice * chemie škodlivé účinky MeSH
- lidé MeSH
- výsledek terapie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- kazuistiky MeSH
Poleptání kůže, ať kyselinou nebo zásadou, patří ke stále častějším pracovním úrazům. Látek, které způsobují poruchu integrity kožního krytu, je nepřeberné množství. Epoxidová pryskyřice, jejíž používání v řadě průmyslových odvětví je dlouhodobě na vzestupu, se i dnes řadí svým výskytem mezi raritní původce kožních postižení. Nízký epidemiologický výskyt je však v kontrastu s možnou mírou postižení. I zde se ukazuje, že jedno z největších úskalí postižení kůže chemikáliemi je jejich dlouhodobá absorpce měkkými tkáněmi. Pokud se úraz a následná léčba navíc zkomplikují nespecifickou hypersenzitivní reakcí při vrozené predispozicí jedince, může se zprvu banální ambulantní rána změnit v dlouhodobě se nehojící defekt vedoucí až k ústavní péči spojené se systémovou léčbou.
Chemical burns represent a frequent cause of an occupational injury. Numerous chemical substances, such as epoxy resin as we reported on in this article, could potentially cause skin damage or, moreover, systemic toxicity. There is an increasing trend in use of epoxy resin in different kinds of industry. Nevertheless, a minimum of occupational diseases are effected by epoxy resin, however, this could be in contrast with the possible severity of the disease. Chemical substances penetrate the human skin and are absorbed by soft tissues for the long time resulting into a major damage of the skin. In this publication we present a case of a chemical burn caused by the epoxy resin and complicated by a severe nonspecific hypersensitive reaction requiring a hospital care and systemic treatment.
- MeSH
- chemické popálení * MeSH
- dospělí MeSH
- dráždivá dermatitida MeSH
- kontaktní dermatitida MeSH
- lidé MeSH
- syntetické pryskyřice * MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- kazuistiky MeSH
Acta dermato-venereologica
80 s. : tab., bibliogr.
The research of novel implantable medical devices is one of the most attractive, yet complex areas in the biomedical field. The design and development of sufficiently small devices working in an in vivo environment is challenging but successful encapsulation of such devices is even more so. Industry-standard methods using glass and titanium are too expensive and tedious, and epoxy or silicone encapsulation is prone to water ingress with cable feedthroughs being the most frequent point of failure. This paper describes a universal and straightforward method for reliable encapsulation of circuit boards that achieves ISO10993 compliance. A two-part PVDF mold was machined using a conventional 3-axis machining center. Then, the circuit board with a hermetic feedthrough was placed in the mold and epoxy resin was injected into the mold under pressure to fill the cavity. Finally, the biocompatibility was further enhanced with an inert P3HT polymer coating which can be easily formulated into an ink. The biocompatibility of the encapsulants was assessed according to ISO10993. The endurance of the presented solution compared to silicone potting and epoxy potting was assessed by submersion in phosphate-buffered saline solution at 37 °C. The proposed method showed superior results to PDMS and simple epoxy potting.
- Klíčová slova
- protargol,
- MeSH
- elektronová mikroskopie MeSH
- epoxidové pryskyřice MeSH
- glykogen MeSH
- mikroskopie MeSH
- stříbrné proteiny MeSH
- MeSH
- barvení a značení MeSH
- elektronová mikroskopie MeSH
- experimenty na zvířatech MeSH
- histocytochemie metody MeSH
- krysa rodu rattus MeSH
- mozek anatomie a histologie ultrastruktura MeSH
- nervová vlákna anatomie a histologie ultrastruktura MeSH
- neurony anatomie a histologie ultrastruktura MeSH
- syntetické pryskyřice MeSH
- Check Tag
- krysa rodu rattus MeSH
