Para-tertiary Butyl Catechol Research Articles

Para-tertiary butyl catechol (PTBC), an industrial antioxidant induces human platelet apoptosis.

The catecholic derivative para-tertiary butyl catechol (PTBC) is a conventional antioxidant and polymerization inhibitor, which exhibits melanocytotoxic effects and contact dermatitis often leading to occupational leucoderma or vitiligo. Although numerous industrial workers will be in constant exposure to PTBC and its chances of getting entry into blood are most expected, its effect on blood components is still undisclosed. As platelets play a prominent role in dermatitis, inflammation, and immunity, in this study we have evaluated the effect of PTBC on human platelets in vitro. Exposure of platelets to PTBC showed increased reactive oxygen species (ROS), intracellular calcium, cardiolipin oxidation, mitochondrial permeability transition pore (MPTP) formation, activation of caspases, phosphatidylserine (PS) externalization and decreased mitochondrial membrane potential. In addition, there was a significant decrease in cellular glutathione level, increased γ-glutamyltransferase (GGT) activity and cell death. These findings demonstrate that PTBC could induce toxic effects on blood components, which is often ignored field of research. Since dermal exposure of humans to toxic chemicals covers an important issue in various industries, there is a need of such work to understand and update the long-term toxicities induced by PTBC usage in industrial sectors and public domain.

Para-tertiary butyl catechol induces eryptosis in vitro via oxidative stress and hemoglobin leakage in human erythrocytes

Exposure of human population to industrial chemicals is believed as a significant contributing factor to the outgrowth of occupational diseases especially in developing countries due to improper safety measures and sanitary conditions. Para-tertiary butylcatechol (PTBC) widely employed in petrochemical, thermofax and phototypesetting industries, induces melanocytotoxicity and contact dermatitis leading to occupational leukoderma/vitiligo. Few vitiligo patients were reported for oxidative stress-induced hemolytic anemia and thrombocytopenia, however its impact on blood components is still not clear. Erythrocytes are the major cell population in circulation and play a prominent role in various diseases. In this work, the effect of PTBC on human erythrocytes is evaluated in vitro. PTBC induces oxidative stress-mediated eryptosis (erythrocyte death) causing detrimental changes such as depleted antioxidant levels, altered surface morphology, hemoglobin denaturation and heinz body formation. These findings validate that PTBC could induce toxic effects on human erythrocytes. Exposure of humans to toxic chemicals constitutes an important issue in various industries; one such issue is the exposure of PTBC at work place resulting in a spectrum of dermal complications. Therefore, it is imperative to appraise the long-term toxicities in order to further delineate the mechanisms of resultant disorders associated with PTBC and to establish the therapeutic interventions.

Reaction Inhibition in the Control of Exothermic Runaway

A research program has been undertaken into the use of chemical inhibition techniques as a basis of safety for the control of exothermic runaway reaction hazards. The principal element of the research has been the design and running of a series of pilot scale trials at the Health and safety Laboratories into the inhibition of an uncontrolled polymerization of styrene have demonstrated the effectiveness of the injection of the inhibitor para tertiary butyl catechol at two different agitation speeds and under conditions immediately following agitation failure. Modeling of the experiments using a network-of-zones approach has shown some inadequacies with the reproduction of the pilot scale data, notably in the inability to simulate the jet mixing effects that dominate in small scale plant with the conditions employed. M The present modeling results do, however, underpredict the mixing efficiency, thereby leading to a more conservative design for the cases studied.

Occupational dermatoses among fibreglass-reinforced plastics factory workers.

Fibreglass-reinforced plastics (FRP) factory workers are at high risk of developing occupational dermatoses because of their exposure to many chemicals used in the manufacture of plastics as well as to glass fibre or dust. Patch tests were carried out on 29 workers involved in FRP manufacturing processes where unsaturated polyester (UP) resin was used, to investigate the causes of their skin problems. Of the 22 workers who reported experiencing skin problems, 16 showed positive results to at least 1 chemical, including 6 cases of multiple sensitivity. 2 showed positive reactions to UP base resin, 6 to cobalt chloride, 5 to benzoyl peroxide (BPO), 4 to methyl ethyl ketone peroxide (MEKPO), 2 to para-tertiary butyl catechol (PTBC), 1 to styrene and 1 to formaldehyde. After taking into account their exposures and reported causes by questionnaires and their patch test results, 7 cases were diagnosed as allergic contact dermatitis (ACD) due to chemicals, 3 as irritant contact dermatitis (ICD) due to chemicals, and 3 as dermatitis due to mechanical irritation (MI) from glass fibre or dust, as well as 9 as ACD and/or MI. 18 of the total of 29 subjects (62.1%), including 2 workers without a history of skin problems, were sensitized to at least 1 chemical. Cobalt, peroxides, PTBC and UP base resin were the common causes of ACD.

Patch test sensitization caused by para-tertiary-butylcatechol. Results of a prospective study with a dilution series.

Para-tertiary-butylcatechol (PTBC) has been patch tested in Europe at 1% in petrolatum (pet.) and is now suspected of induction of patch test sensitization. A prospective study was initiated to obtain detailed data on this undesirable risk. A dilution series of PTBC (1%, 0.5%, 0.25%, 0.1% pet.) was used. Patch tests were read on days (D) 1-3, 7, 14 and 21 after application. Patients who were unable to return for late readings were telephoned and asked to report any reaction at the patch test sites. 40 out of 46 patients included completed the study. Patch tests were negative in 35 patients. 4 patients showed a positive patch test at later readings only (D7-D21); 2 patients reacted to a concentration as low as 0.1%. Rechallenge was performed in 2 of these patients, revealing a clearly positive reaction as early as D2 after patch test application. PTBC clearly induced patch test sensitization in 10% of the patients. It cannot be excluded that patch testing with 0.25% PTBC or with even lower concentrations might induce patch test sensitization. The optimal patch test concentration still has to be determined but may be within the range of 0.01% to 0.25% PTBC.

Active sensitization and occupational allergic contact dermatitis caused by para-tertiary-butylcatechol.

Para-tertiary-butylcatechol (PTBC) is a rare allergen which is used in the rubber, paint and petroleum industries. We present 9 patients who were sensitized to PTBC and examined at the Finnish Institute of Occupational Health (FIOH) between 1974 and 1995. 3 of the patients had been exposed to PTBC in their work. 2 of them also had allergic reactions to para-tertiary-butylphenol (PTBP)-formaldehyde resin and to PTBP. 5 of the patients became sensitized to PTBC from patch testing. PTBC was found to be one of the most common causes of active sensitization in our clinic. Accordingly, at the FIOH, the patch test concentration of PTBC was lowered to 0.25% and this lower concentration is recommended for general use.

Ocupational vitiligo and contact sensitivity to para‐tertiary butyl catechol

Contact DermatitisVolume 25, Issue 3 p. 200-201 Ocupational vitiligo and contact sensitivity to para-tertiary butyl catechol David J. Gawkrodger, David J. Gawkrodger University Department of Dermatology, Royal Hallamshire Hospital, Sheffield S10 2JF, UKSearch for more papers by this authorMichel J. Cork, Michel J. Cork University Department of Dermatology, Royal Hallamshire Hospital, Sheffield S10 2JF, UKSearch for more papers by this authorStanley S. Bleehen, Stanley S. Bleehen University Department of Dermatology, Royal Hallamshire Hospital, Sheffield S10 2JF, UKSearch for more papers by this author David J. Gawkrodger, David J. Gawkrodger University Department of Dermatology, Royal Hallamshire Hospital, Sheffield S10 2JF, UKSearch for more papers by this authorMichel J. Cork, Michel J. Cork University Department of Dermatology, Royal Hallamshire Hospital, Sheffield S10 2JF, UKSearch for more papers by this authorStanley S. Bleehen, Stanley S. Bleehen University Department of Dermatology, Royal Hallamshire Hospital, Sheffield S10 2JF, UKSearch for more papers by this author First published: September 1991 https://doi.org/10.1111/j.1600-0536.1991.tb01838.xCitations: 17AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL No abstract is available for this article.Citing Literature Volume25, Issue3September 1991Pages 200-201 RelatedInformation