Evolutionarily adapted hormesis-inducing stressors can be a practical solution to mitigate harmful effects of chronic exposure to low dose chemical mixtures

Kim, Se-A.,Lee, Yu-Mi,Choi, Je-Yong,Jacobs Jr., David R.,Lee Jr., Duk-Hee Elsevier 2018 Environmental pollution Vol.233 No.-

<P><B>Abstract</B></P> <P>Although the toxicity of synthetic chemicals at high doses is well known, chronic exposure to low-dose chemical mixtures has only recently been linked to many age-related diseases. However, it is nearly impossible to avoid the exposure to these low-dose chemical mixtures as humans are exposed to a myriad of synthetic chemicals as a part of their daily lives. Therefore, coping with possible harms due to low dose chemical mixtures is challenging. Interestingly, within the range of environmental exposure, disease risk does not increase linearly with increasing dose of chemicals, but often tends to plateau or even decrease with increasing dose. Hormesis, the over-compensation of various adaptive responses through cellular stresses, is one possible mechanism for this non-linearity. Although the hormetic effects of synthetic chemicals or radiation have long been debated in the field of toxicology, the hormesis concept has recently been generalized in the field of molecular biology; similar to responses to synthetic chemicals, mild to moderate intermittent stressors from any source can induce hormetic responses. Examples of stressors are exercise, calorie restriction, intermittent fasting, cognitive stimulation, and phytochemicals. Mitohormesis is hormesis induced by such stressors through mitochondrial retrograde signalling including the increased production of mild reactive oxygen species. Xenohormesis is phytochemical-induced hormesis, reflective of a mutualistic relationship between plant and animals. As humans had repeated exposure to all of these stressors during their evolution, the hormetic effects of these health behaviours may be considered to be evolutionarily adapted. Although hormesis induced by synthetic chemicals occurs in humans, such hormesis may not be recommended to the public due to unresolved issues on safety including the impossibility of control exposure. However, the use of personal health behaviors which enhance mitohormetic- or xenohormetic-stress can be readily incorporated into everyone's daily lives as a practical way to counteract harmful effects of unavoidable low-dose chemical mixtures.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Chronic exposure to low-dose chemical mixtures may be harmful in humans. </LI> <LI> Within the low dose range, the risk of diseases does not linearly increase. </LI> <LI> Hormesis is a possible mechanism for the non-linearity of low dose range. </LI> <LI> Hormesis induced by synthetic chemicals has unresolved issues on safety. </LI> <LI> Hormesis-inducing stressors with evolutionary adaptation can be a practical solution. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Evidence of the Possible Harm of Endocrine-Disrupting Chemicals in Humans: Ongoing Debates and Key Issues

이덕희 대한내분비학회 2018 Endocrinology and metabolism Vol.33 No.1

Evidence has emerged that endocrine-disrupting chemicals (EDCs) can produce adverse effects, even at low doses that are assumedsafe. However, systemic reviews and meta-analyses focusing on human studies, especially of EDCs with short half-lives, have demonstratedinconsistent results. Epidemiological studies have insuperable methodological limitations, including the unpredictable neteffects of mixtures, non-monotonic dose-response relationships, the non-existence of unexposed groups, and the low reliability of exposureassessment. Thus, despite increases in EDC-linked diseases, traditional epidemiological studies based on individual measurementsof EDCs in bio-specimens may fail to provide consistent results. The exposome has been suggested as a promising approach toaddress the uncertainties surrounding human studies, but it is never free from these methodological issues. Although exposure toEDCs during critical developmental periods is a major concern, continuous exposure to EDCs during non-critical periods is also harmful. Indeed, the evolutionary aspects of epigenetic programming triggered by EDCs during development should be considered becauseit is a key mechanism for developmental plasticity. Presently, living without EDCs is impossible due to their omnipresence. Importantly,there are lifestyles which can increase the excretion of EDCs or mitigate their harmful effects through the activation of mitohormesisor xenohormesis. Effectiveness of lifestyle interventions should be evaluated as practical ways against EDCs in the real world.

산업안전보건법 상 유해성 위험성 평가제도 적용을 위한 양-반응 평가의 통일화 방안 연구

임철홍 ( Cheol Hong Lim ),양정선 ( Jeong Sun Yang ),박상용 ( Sang Yong Park ) 한국산업위생학회 2012 한국산업보건학회지 Vol.22 No.3

Objectives: This study developed a harmonized method for risk assessment based on the Hazard & Risk Evaluation of Chemicals (HREC) according to the Industrial Safety and Health Act (ISHA). Methods: Three preliminary studies, performed during 2010 and 2011 by the Occupational Safety and Health Research Institute and three academic research groups, were compared. The differences in risk assessment, especially in the dose-response assessment method, were analyzed. A new harmonized method for dose-response assessment was suggested and its applicability for the HREC was examined. Results:: Considering the various steps of each dose-response assessment, the equivalent steps in quantitative correction, uncertainty factor 2 (UF2) for intra-species uncertainty, and UF3 for the experimental period in the uncertainty correction were relatively high. Using our new method, the total correction values (quantitative correction plus uncertainty correction) ranged from 72~15,789 to 30~60, and the ratio of the threshold limit value (TLV) to the reference concentration decreased from 12.8~1900 to 5.4~11.8. Furthermore, when we performed risk characterization by our new method, hazard quotient (HQ) values for chloroethylene, epichlorohydrin, and barium sulfate became 3.0, 14.1, and 1.13 respectively, whereas three previous studies reported HQ values of 7.1, 4580, and 87.3 considering reasonable maximum exposure (RME) conditions. HQs of the three chemicals were calculated to be 0.6, 2.4, and 0.1 respectively, when compared to their TLVs. Conclusions: Our new method could be applicable for the HREC because the total correction values and the ratio of TLVs were within reasonable ranges. It is also recommended that additional risk management measures be applied for epichlorohydrin, for which the HQ values were greater than 1 when compared with both reference values and the TLV. Our proposed method could be used to harmonize dose-response assessment methods for the implementation of risk assessment based on the HREC according to ISHA

Chemical Dosing Control for Ultrafiltration Water Treatment System

P. Kungwalrut,A. Numsomran,P. Chaiyasith,J. Chaoraingern,V. Tipsuwanporn 제어로봇시스템학회 2017 제어로봇시스템학회 국제학술대회 논문집 Vol.2017 No.10

Chemical dosing is a significant process of water treatment system because it influences on water quality and operational cost. This paper presents a chemical dosing pH control using temporal logic technique for ultrafiltration water treatment system, in order to validate and analyze an appropriate control approach. In this study, a simulation was built in Matlab Simulink, and has been tested with the data collected from a pilot-scale ultrafiltration water treatment system. As stated in the simulation results, the proposed control scheme can achieve the performance specification in pH control.

Effects of intermittent chemical dosing on volatile sulfur compounds in sewer headspace

Guijiao Zhang,Tianfeng Gu,Yongchao Zhou,David Z. Zhu,Yiping Zhang 대한환경공학회 2022 Environmental Engineering Research Vol.27 No.3

Volatile sulfur compounds (VSCs), including hydrogen sulfide (H₂S) and volatile organic sulfide compounds (VOSCs), can be produced in sewer systems causing sewer odor problems. In this study, the effects of intermittently dosing ferric iron, hydrogen peroxide, and nitrate on H₂S and VOSCs in sewer headspace were investigated. In order to characterize the composition of VSCs, an HC-3 trace sulfur analyzer and gas chromatograph (GC) equipped with a triple quadrupole-type mass spectrometry (MS) apparatus were used to determine the VSCs. The results indicated that the effect of intermittent addition of 40 mg/L ferric iron or 40 mg/L hydrogen peroxide is limited for VSCs inhibition. The H₂S and VOSCs concentrations increased significantly in the late-stage experiments, even around 20% and 30% respectively higher than the initial average concentrations. However, the intermittent addition of 40 mg N/L nitrate has a relatively stable control effect of H₂S and VOSCs which maintaining 60% removal rate. Moreover, methyl mercaptan (MeSH) was the most abundant compound of the total VOSCs released and the results of the theoretical odor concentration study also indicate MeSH is the main VOSC causing the significant odor problem. Therefore, more attention should be focused on the VOSCs which have extremely low odor threshold.

국내 원전주변 주민 방사선 피폭선량 평가-입력변수의 영향

조대철,이갑복 한국산학기술학회 2003 한국산학기술학회논문지 Vol.4 No.3

ICRP-60 신권고에 맞게 수정된 방사선피폭선량 계산프로그램인 K-DOSE 60을 4개 발전소 (고리, 월성, 울진, 영광)에 적용하여 주변주민 최대개인피폭선량을 평가하였다. 핵종, 장기, 경로별로 결정변수값들을 도출한 결과, 경로는 성인의 경우 농작물, 유아의 경우 우유가, 핵종은 ³H, ¹³³Xe, ⁶⁰CO (고리 1,2발전소), ¹⁴C, ⁴¹Ar(월성 1,2발전소)로 나타났으며, 모든 장기에 대한 피폭선량차이가 매우 작았다. “출력 대 입력” 변통에 근거한 민감도 분석결과, 핵종의 화학적 형태가 타 입력변수들보 다 10² factor만큼 높은 민감도를 보였으며, 전이/농축계수에 의한 민감도는 섭취량이나 방출량의 그것에 비하여 상대적으로 매우 낮았다. PCC를 이용한 상관성 민감도의 경우는 4가지 입력변수 모두 0.97 이상의 높은 상관성을 보였다. Annual radiation dose of residential individuals near 4 nuclear power plants in Korea was calculated via KDOSE 60 based on the updated ICRP-60. The critical exposure variables were chosen as radionuclides, exposed organs and intake pathways. From the calculation results, the critical nuclides were found to be ³H, ¹³³Xe, ⁶⁰CO for Kori plants and ¹⁴C, ⁴¹Ar for Wolsung plants. The most critical pathway was ‘vegetable intake’ for adults and ‘milk intake’ for infants. However, there was no preference in the effective organs. Sensitivity analyses showed that the chemical composition in a nuclide much more influenced upon the radiation dose than any other input parameters such as food intake, radiation discharge, and transfer/concentration coefficients by more than 10² factor. The effect of transfer/ concentration coefficients on the radiation dose was negligible. All input parameters showed highly estimated correlation with the radiation dose, approximated to 1.0.

복숭아 저장성 증진을 위한 저선량의 UV-C 조사 효과

이경행 ( Kyung Haeng Lee ),박재희 ( Jae Hee Park ),이유진 ( Yu Jin Lee ),반기은 ( Ki Eun Ban ),장주희 ( Joo Hee Jang ) 한국식품영양학회 2013 韓國食品營養學會誌 Vol.26 No.1

국내산 복숭아의 저장성 증진을 위하여 저선량(0∼3.0kJ/㎡)의 UV-C를 조사하고, 저장기간 동안 부패율, 이화학적 변화 및 기호도의 변화를 측정하였다. 부패율의 경우, 대조군은 4일 이후부터는 부패된 복숭아를 보이기 시작하였으며, 저장 8일에는 50.00%의 부패율을 나타내었다. 저선량의 UV-C 처리군은 대조군보다 낮은 부패율을 보였으며, 특히 1.0 및 2.0kJ/㎡의 UV-C 처리군이 가장 낮은 부패율을 나타내었다. 무게 변화의 경우, 대체적으로 대조군 및 UV-C 처리군 모두 저장기간 동안 큰 차이를 보이지는 않았다. pH 변화에서는 UV-C 처리에 의한 차이를 보이지 않았으며, 저장기간 중 pH가 증가하였으나 모든 실험군에서 차이가 없는 것으로 나타났다. 경도의 경우, UV-C 처리 직후에는 모든 실험군에서 차이가 없었으나, 저장 중 대조군의 변화가 가장 많았으며, UV-C 처리군의 경도 변화는 적은 것으로 나타났다. 색도 변화(명도, 적색도 및 황색도)에서는 UV-C 처리 및 저장 중 모든 실험군에서 큰 차이를 보이지는 않는 것으로 나타났다. 맛, 향, 색에 대한 기호도의 변화에서는 UV-C 처리에 의한 변화를 보이지 않았으며, 저장 중 기호도는 감소하였으나 모든 실험군에서 차이가 없는 것으로 나타났다. 조직감 및 종합적 기호도에서는 UV-C 처리에 의한 변화를 보이지 않았으나 저장 중 대조군의 기호도값이 가장 많이 감소하였고, UV-C 처리군의 변화는 적은 것으로 나타났다. 전반적으로 대조군보다는 저선량의 UV-C 처리군이 기호도가 높은 것으로 나타났다. For shelf-life improvement of the domestic peach, a treatment with low dose UV-C (0∼3.0kJ/㎡) irradiation was performed and the spoilage rate and changes of physico-chemical and sensory properties of the peach were investigated. Control showed spoilage at day 4, and then 50% of control showed spoilage at day 8. However, samples treated with low dose UV-C showed lower percentage of spoilage than those of control at day 8. Weight changes of control and the samples with UV-C treatment showed no difference during the storage period. There was no difference in pH of samples among the treatments but they were increased by storage time. Hardness of samples was not different among treatments at initial stage of storage after UV-C treatment. However, the hardness of control sample was decreased faster than those of the samples with low dose UV-C treatment after 6 days of storage. No significant changes in lightness, redness and yellowness of the samples by UV-C treatment were observed. The sensory parameters including taste, flavor, and color at initial and during storage period were not different among treatments except for texture and overall acceptance. The scores for texture and overall acceptance of control were decreased faster than those of UV-C treatments during storage. In general, samples treated with low dose UV-C showed higher sensory quality than control.

화학물질의 건강위험성과 냄새 역치

윤충식(Chungsik Yoon) 서울대학교 보건환경연구소 2016 보건학논집 Vol.53 No.2

Results: Among the 656 chemicals having Korean OELs, 123 chemicals had odor threshold values. There were no correlation (R<SUP>2</SUP>=0.0036) between 8-hour Time Weighted Average(TWA) and odor threshold values in 112 chemicals which had both 8-hour TWA and odor threshold values. This fact means that health hazard could not be judged by sense of smell in the workplace or other environment. The classification of the chemicals having odor threshold values into three categories, the ones which had higher odor threshold values than OELs, the ones had lower odor threshold values than OELs and the ones having similar values, could be used to manage chemicals at the workplace. Three chemicals like decaborane(0.05ppm), formaldehyde(0.5ppm), and hydrogen fluoride(0.5ppm) had the same value of 8hr-TWA and odor threshold values. The correlations of odor threshold with vapor pressure (R<SUP>2</SUP>=0.0024), with LD<SUB>50</SUB>(R<SUP>2</SUP>=0.0043), and with LC<SUB>50</SUB>(R<SUP>2</SUP>=0.0025), were weak. Though it is very difficult to elucidate the relationship between odor threshold and chemical structure or its reactive group, this study showed several structural similarities and reactive groups for chemicals having very low odor threshold values. Conclusion: This study found that there were no correlation between odor thresholds and health hazards using index such as OELs(R<SUP>2</SUP>=0.06), LD<SUB>50</SUB> (R<SUP>2</SUP>=0.004) and LC<SUB>50</SUB>(R<SUP>2</SUP>=0.003). There was moderate correlation between OELs (R<SUP>2</SUP>=0.16) and LD<SUB>50</SUB>(R<SUP>2</SUP>=0.38), between OELs and LC50(R2=0.14).

연구논문 : 저선량의 UV-C 처리 복숭아의 주요 성분 변화

이경행 ( Kyung Haeng Lee ),장현정 ( Hyun Jung Jang ),최지혜 ( Ji Hye Choi ),반기은 ( Ki Eun Ban ),박재희 ( Jae Hee Park ),이유진 ( Yu Jin Lee ) 한국식품영양학회 2013 韓國食品營養學會誌 Vol.26 No.3

국내산 복숭아의 저장성 증진을 위하여 저선량(0~3.0 kJ/m2)의 UV-C를 조사하고, 저장 중 주요 성분의 변화를 측정하였다. Polyphenol 화합물 함량은 UV 처리시 대조군에 비햐여 약간 높은 함량을 보이는 것으로 나타났다. 특히 0.25 KJ/m2 처리군은 가장 많은 함량을 나타내었다. 저장 과정 중의 polyphenol 화합물의 함량은 대조군 및 UV 처리군 모두 서서히 감소하는 경향이었다. Flavonoid 함량은 대조군 및 UV 처리군 모두 저장하는 동안 특정한 경향을 나타내지는 않는 것으로 나타났다. 복숭아 내 유리당은 UV 처리군 및 대조군 모두 fructose, glucose, maltose 및 sucrose가 검출되었고, 이중 sucrose의 함량이 가장 많았으며, 저장 중 당 함량은 증가하였으며, UV 처리군 및 대조군 모두 유의적인 차이를 보이지 않았다. 유리아미노산은 대조군은 115.38 mg%였으며, UV-C처리군의 경우, 총 유리아미노산의 함량은 95.92~120.94 mg%로 함량의 차이가 약간 있긴 하지만 유의적인 차이를 보이지 않아, 저선량의 UV-C 처리는 가능할 것으로 판단되었다. To extend the shelf-life of the domestic peach, a low dose UV-C irradiation (0~3.0 kJ/㎡) was treated and the changes of the major chemical components were investigated. The contents of polyphenols in UV-treated peaches were higher than that of control with the highest at 0.25 kJ/㎡ UV treatment. The contents of polyphenols of control and UV treatments were slightly reduced by storage period. The contents of flavonoid were not significantly different among the control and UV treatments. Detected free sugars of the control and UV treatments were fructose, glucose, maltose and sucrose. Sucrose content was higher than that of other free sugars and free sugar content increased during storage. And free sugar content was not significantly different between the control and UV treatments. The free amino acid content of the control and UV treatments were 115.38 ㎎% and 95.92~120.94 ㎎% respectively, but there was no significant difference between the control and UV treatments.

Applied to reuse steam condensate water in Medium petrochemical plant to boiler feed water

S. Tammaruckwattana,A. Seekhieo,N. Tammarugwattana 제어로봇시스템학회 2022 제어로봇시스템학회 국제학술대회 논문집 Vol.2022 No.11

In Thailands petrochemical industrial estate which has a small or medium-size plant, boiler feed water is bought from the external boiler feed water provider to use in an incinerator to make steam for plant use, and the steam condensate water that comes after the incinerator process is sold back to the provider as well. The cost gap between bought water and sold water is considered a waste since the income gained from selling post-boiled water is less than expenses from bought water. In this paper, the research to improve the steam condensate water quality and reuse the water has been proposed. This application is to be considered to build the steam condensate treatment unit for treating water potential to reduce the overall operation cost (OPEX). The online analyzer is being used to control the chemical dosing package via a plant control system to check the quality of water and treat it in real-time so the water can be reused.