scholarly journals Generation of hydrogen peroxide from San Joaquin Valley particles in a cell-free solution

2010 ◽  
Vol 10 (9) ◽  
pp. 21323-21356 ◽  
Author(s):  
H. Shen ◽  
A. I. Barakat ◽  
C. Anastasio
Keyword(s):  
Hydrogen Peroxide ◽  
Health Effects ◽  
Dominant Role ◽  
Epidemiological Studies ◽  
San Joaquin Valley ◽  
Ambient Particulate Matter ◽  
Adverse Health Effects ◽  
Human Lungs ◽  
A Cell ◽  
Phosphate Buffered Saline

Abstract. Epidemiological studies have shown a correlation between exposure to ambient particulate matter (PM) and adverse health effects. One proposed mechanism of PM-mediated health effects is the generation of reactive oxygen species (ROS) – e.g., superoxide (•O2−), hydrogen peroxide (HOOH), and hydroxyl radical (•OH) – followed by oxidative stress. There are very few quantitative, specific measures of individual ROS generated from PM, but this information would help to more quantitatively address the link between ROS and the health effects of PM. To address this gap, we quantified the generation of HOOH by PM collected at an urban (Fresno) and rural (Westside) site in the San Joaquin Valley (SJV) of California during summer and winter from 2006 to 2009. HOOH was quantified by HPLC after extracting the PM in a cell-free, phosphate-buffered saline (PBS) solution with or without 50 μM ascorbate (Asc). Our results show that the urban PM generally generates much more HOOH than the rural PM but that there is no apparent seasonal difference in HOOH generation. In nearly all of the samples the addition of a physiologically relevant concentration of Asc greatly enhances HOOH formation, but a few of the coarse PM samples were able to generate a considerable amount of HOOH in the absence of added Asc, indicating the presence of unknown reductants. Normalized by air volume, the fine PM (PM2.5) generally makes more HOOH than the corresponding coarse PM (PMcf, i.e., 2.5 to 10 μm), primarily because the mass concentration of PM2.5 is much higher than that of PMcf. However, normalized by PM mass, the coarse PM typically generates more HOOH than the fine PM. The amount of HOOH produced by SJV PM is reduced on average by (78±15)% when the transition metal chelator desferoxamine (DSF) is added to the extraction solution, indicating that transition metals play a dominant role in HOOH generation. By measuring calibration curves of HOOH generation from copper, and quantifying copper concentrations in our particle extracts, we find that PBS-soluble copper is primarily responsible for HOOH production by the Fresno PM. Extrapolating our results to expected concentrations of PM-derived HOOH in human lungs suggests that typical daily PM exposures in the San Joaquin Valley are unlikely to cause HOOH-mediated acute health effects, but that very high PM events might lead to cytotoxic levels of pulmonary HOOH.

scholarly journals Generation of hydrogen peroxide from San Joaquin Valley particles in a cell-free solution

2011 ◽  
Vol 11 (2) ◽  
pp. 753-765 ◽  
Author(s):  
H. Shen ◽  
A. I. Barakat ◽  
C. Anastasio
Keyword(s):  
Hydrogen Peroxide ◽  
Health Effects ◽  
Dominant Role ◽  
Epidemiological Studies ◽  
San Joaquin Valley ◽  
Ambient Particulate Matter ◽  
Adverse Health Effects ◽  
A Cell ◽  
Lung Lining Fluid ◽  
Phosphate Buffered Saline

Abstract. Epidemiological studies have shown a correlation between exposure to ambient particulate matter (PM) and adverse health effects. One proposed mechanism of PM-mediated health effects is the generation of reactive oxygen species (ROS) – e.g., superoxide (•O2−), hydrogen peroxide (HOOH), and hydroxyl radical (•OH) – followed by oxidative stress. There are very few quantitative, specific measures of individual ROS generated from PM, but this information would help to more quantitatively address the link between ROS and the health effects of PM. To address this gap, we quantified the generation of HOOH by PM collected at an urban (Fresno) and rural (Westside) site in the San Joaquin Valley (SJV) of California during summer and winter from 2006 to 2009. HOOH was quantified by HPLC after extracting the PM in a cell-free, phosphate-buffered saline (PBS) solution with or without 50 μM ascorbate (Asc). Our results show that the urban PM generally generates much more HOOH than the rural PM but that there is no apparent seasonal difference in HOOH generation. In nearly all of the samples the addition of a physiologically relevant concentration of Asc greatly enhances HOOH formation, but a few of the coarse PM samples were able to generate a considerable amount of HOOH in the absence of added Asc, indicating the presence of unknown reductants. Normalized by air volume, the fine PM (PM2.5) generally makes more HOOH than the corresponding coarse PM (PMcf, i.e., 2.5 to 10 μm), primarily because the mass concentration of PM2.5 is much higher than that of PMcf. However, normalized by PM mass, the coarse PM typically generates more HOOH than the fine PM. The amount of HOOH produced by SJV PM is reduced on average by (78 ± 15)% when the transition metal chelator desferoxamine (DSF) is added to the extraction solution, indicating that transition metals play a dominant role in HOOH generation. By measuring calibration curves of HOOH generation from copper, and quantifying copper concentrations in our particle extracts, we find that PBS-soluble copper is primarily responsible for HOOH production by the Fresno PM. Extrapolating our results to expected concentrations of PM-derived HOOH in human lung lining fluid suggests that typical daily PM exposures in the San Joaquin Valley are unlikely to cause HOOH-mediated acute health effects, but that very high PM events might lead to cytotoxic levels of pulmonary HOOH.

scholarly journals Formation of hydroxyl radical from San Joaquin Valley particles extracted in a cell-free solution

2011 ◽  
Vol 11 (6) ◽  
pp. 16861-16894 ◽  
Author(s):  
H. Shen ◽  
C. Anastasio
Keyword(s):  
Hydroxyl Radical ◽  
Dominant Role ◽  
San Joaquin Valley ◽  
Ambient Particulate Matter ◽  
Adverse Health Effects ◽  
Quantitative Studies ◽  
A Cell ◽  
Lung Lining Fluid ◽  
Phosphate Buffered Saline

Abstract. Previous studies have suggested that the adverse health effects from ambient particulate matter (PM) are linked to the formation of reactive oxygen species (ROS) by PM. While hydroxyl radical (•OH) is the most reactive of the ROS species, there are few quantitative studies of •OH generation from PM. Here we report on •OH formation from PM collected at an urban (Fresno) and rural (Westside) site in the San Joaquin Valley (SJV) of California. We quantified •OH in PM extracts using a cell-free, phosphate-buffered saline (PBS) solution with or without 50 μM ascorbate (Asc). The results show that generally the urban Fresno PM generates much more •OH than the rural Westside PM. The presence of Asc at a physiologically relevant concentration in the extraction solution greatly enhances •OH formation from all the samples. Fine PM (PM2.5) generally makes more •OH than the corresponding coarse PM (PMcf, i.e., 2.5 to 10 μm) normalized by air volume collected, while the coarse PM typically generates more •OH normalized by PM mass. •OH production by SJV PM is reduced on average by (97 ± 6) % when the transition metal chelator desferoxamine (DSF) is added to the extraction solution, indicating a dominant role of transition metals. By measuring calibration curves of •OH generation from copper and iron, and quantifying copper and iron concentrations in our particle extracts, we find that PBS-soluble copper is primarily responsible for •OH production by the SJV PM, while iron often makes a significant contribution. Extrapolating our results to expected burdens of PM-derived •OH in human lung lining fluid suggests that typical daily PM exposures in the San Joaquin Valley are unlikely to result in a high amount of pulmonary •OH, although high PM events could produce much higher levels of •OH, which might lead to cytotoxicity.

scholarly journals Formation of hydroxyl radical from San Joaquin Valley particles extracted in a cell-free surrogate lung fluid

2011 ◽  
Vol 11 (18) ◽  
pp. 9671-9682 ◽  
Author(s):  
H. Shen ◽  
C. Anastasio
Keyword(s):  
Hydroxyl Radical ◽  
Dominant Role ◽  
San Joaquin Valley ◽  
Lung Fluid ◽  
Adverse Health Effects ◽  
Quantitative Studies ◽  
A Cell ◽  
Lung Lining Fluid ◽  
Phosphate Buffered Saline

Abstract. Previous studies have suggested that the adverse health effects from ambient particulate matter (PM) are linked to the formation of reactive oxygen species (ROS) by PM in cardiopulmonary tissues. While hydroxyl radical (•OH) is the most reactive of the ROS species, there are few quantitative studies of •OH generation from PM. Here we report on •OH formation from PM collected at an urban (Fresno) and rural (Westside) site in the San Joaquin Valley (SJV) of California. We quantified •OH in PM extracts using a cell-free, phosphate-buffered saline (PBS) solution with or without 50 μM ascorbate (Asc). The results show that generally the urban Fresno PM generates much more •OH than the rural Westside PM. The presence of Asc at a physiologically relevant concentration in the extraction solution greatly enhances •OH formation from all the samples. Fine PM (PM2.5) generally makes more •OH than the corresponding coarse PM (PMcf, i.e. with diameters of 2.5 to 10 μm) normalized by air volume collected, while the coarse PM typically generates more •OH normalized by PM mass. •OH production by SJV PM is reduced on average by (97 ± 6) % when the transition metal chelator desferoxamine (DSF) is added to the extraction solution, indicating a dominant role of transition metals. By measuring calibration curves of •OH generation from copper and iron, and quantifying copper and iron concentrations in our particle extracts, we find that PBS-soluble copper is primarily responsible for •OH production by the SJV PM, while iron often makes a significant contribution. Extrapolating our results to expected burdens of PM-derived •OH in human lung lining fluid suggests that typical daily PM exposures in the San Joaquin Valley are unlikely to result in a high amount of pulmonary •OH, although high PM events could produce much higher levels of •OH, which might lead to cytotoxicity.

scholarly journals The Effect of Different Boiling and Filtering Devices on the Concentration of Disinfection By-Products in Tap Water

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Glòria Carrasco-Turigas ◽  
Cristina M. Villanueva ◽  
Fernando Goñi ◽  
Panu Rantakokko ◽  
Mark J. Nieuwenhuijsen
Keyword(s):  
Drinking Water ◽  
Health Effects ◽  
Reverse Osmosis ◽  
Tap Water ◽  
Epidemiological Studies ◽  
The Other ◽  
Large Decrease ◽  
Adverse Health Effects ◽  
Before And After ◽  
By Products

Disinfection by-products (DBPs) are ubiquitous contaminants in tap drinking water with the potential to produce adverse health effects. Filtering and boiling tap water can lead to changes in the DBP concentrations and modify the exposure through ingestion. Changes in the concentration of 4 individual trihalomethanes (THM4) (chloroform (TCM), bromodichloromethane (BDCM), dibromochloromethane (DBCM), and bromoform (TBM)), MX, and bromate were tested when boiling and filtering high bromine-containing tap water from Barcelona. For filtering, we used a pitcher-type filter and a household reverse osmosis filter; for boiling, an electric kettle, a saucepan, and a microwave were used. Samples were taken before and after each treatment to determine the change in the DBP concentration. pH, conductivity, and free/total chlorine were also measured. A large decrease of THM4 (from 48% to 97%) and MX concentrations was observed for all experiments. Bromine-containing trihalomethanes were mostly eliminated when filtering while chloroform when boiling. There was a large decrease in the concentration of bromate with reverse osmosis, but there was a little effect in the other experiments. These findings suggest that the exposure to THM4 and MX through ingestion is reduced when using these household appliances, while the decrease of bromate is device dependent. This needs to be considered in the exposure assessment of the epidemiological studies.

scholarly journals Review of epidemiological studies on air pollution and health effects in children

2021 ◽  
Vol 64 (1) ◽  
pp. 3-11
Author(s):  
Jong-Tae Lee
Keyword(s):  
Air Pollution ◽  
Health Effects ◽  
Respiratory Health ◽  
Ambient Air ◽  
Epidemiological Studies ◽  
Ambient Air Pollution ◽  
Neurodevelopmental Outcomes ◽  
Critical Window ◽  
Adverse Health Effects ◽  
Adverse Health

There is a growing body of literature on the adverse health effects of ambient air pollution. Children are more adversely affected by air pollution due to their biological susceptibility and exposure patterns. This review summarized the accumulated epidemiologic evidence with emphasis on studies conducted in Korea and heterogeneity in the literature. Based on systematic reviews and meta-analyses, there is consistent evidence on the association between exposure to ambient air pollution and children’s health, especially respiratory health and adverse birth outcomes, and growing evidence on neurodevelopmental outcomes. Despite these existing studies, the mechanism of the adverse health effects of air pollution and the critical window of susceptibility remain unclear. There is also a need to identify causes of heterogeneity between studies in terms of measurement of exposure/outcome, study design, and the differential characteristics of air pollutants and population.

scholarly journals Estimates of PI*S and PI*Z Alpha-1 antitrypsin deficiency alleles prevalence in the Caribbean and North, Central and South America

2016 ◽  
Vol 71 (3) ◽  
Author(s):  
F.J. De Serres ◽  
I. Blanco ◽  
E. Fernández-Bustillo
Keyword(s):  
At Risk ◽  
South America ◽  
Health Effects ◽  
Genetic Disorder ◽  
Epidemiological Studies ◽  
North Central ◽  
Screening Programs ◽  
Adverse Health Effects ◽  
Adverse Health ◽  
The Caribbean

Background. AAT deficiency is not a rare disease, but one of the most common congenital disorders increasing susceptibility of individuals with this deficiency to both lung and liver disease as well as other several adverse health effects. Studies to develop accurate estimates of the magnitude of this genetic disorder in any given country is critical for the development of screening programs for detection, diagnosis, and treatment of those individuals and/or families at risk. In the present study, estimates of the prevalence of the two major deficiency alleles PI S and PI Z were estimated for 25 countries in the Caribbean and North, Central, and South America to supplement our previous studies on 69 countries worldwide. Method. Using data on the prevalence of the two most common deficiency alleles PI S and PIZ in the mother countries that provided the majority of immigrants to these 25 countries, as well as genetic epidemiological studies on various genetic subgroups indigenous to the Caribbean and North, Central and South America it was possible to develop new formulas to estimate the numbers in each of five phenotypic classes, namely PI MS, PI MZ, PI SS, PI SZ and PI ZZ for each country. Results. When these 25 countries were grouped into six different geographic regions, the present study demonstrated striking differences when comparisons were made in numeric tables, maps and figures. Highly significant numbers of individuals at risk for AAT Deficiency were found in both the European, Mestizo and Mulatto populations for most of the 25 countries studied in the Caribbean and North, Central and South America. Conclusions. Our studies demonstrated striking differences in the prevalence of both the PIS and PIZ alleles among these 25 countries in the Caribbean and North, Central and South America and significant numbers of individuals at risk for adverse health effects associated with AAT Deficiency in a given country. When these data are added to the results from our earlier studies on 69 countries, we now have data on AAT Deficiency in 94 of the 193 countries worldwide listed in the CIA FactBook.

scholarly journals Ambient and household air pollution: complex triggers of disease

2014 ◽  
Vol 307 (4) ◽  
pp. H467-H476 ◽  
Author(s):  
Stephen A. Farmer ◽  
Timothy D. Nelin ◽  
Michael J. Falvo ◽  
Loren E. Wold
Keyword(s):  
Air Pollution ◽  
Health Effects ◽  
Air Pollutants ◽  
Epidemiological Studies ◽  
World Health ◽  
Outdoor Air ◽  
Rapid Urbanization ◽  
Adverse Health Effects ◽  
Adverse Health ◽  
Indoor And Outdoor

Concentrations of outdoor air pollution are on the rise, particularly due to rapid urbanization worldwide. Alternatively, poor ventilation, cigarette smoke, and other toxic chemicals contribute to rising concentrations of indoor air pollution. The World Health Organization recently reported that deaths attributable to indoor and outdoor air pollutant exposure are more than double what was originally documented. Epidemiological, clinical, and animal data have demonstrated a clear connection between rising concentrations of air pollution (both indoor and outdoor) and a host of adverse health effects. During the past five years, animal, clinical, and epidemiological studies have explored the adverse health effects associated with exposure to both indoor and outdoor air pollutants throughout the various stages of life. This review provides a summary of the detrimental effects of air pollution through examination of current animal, clinical, and epidemiological studies and exposure during three different periods: maternal (in utero), early life, and adulthood. Additionally, we recommend future lines of research while suggesting conceivable strategies to curb exposure to indoor and outdoor air pollutants.

Health effects of nanomaterials

2007 ◽  
Vol 35 (3) ◽  
pp. 527-531 ◽  
Author(s):  
T.D. Tetley
Keyword(s):  
Health Effects ◽  
Animal Studies ◽  
High Surface ◽  
Epidemiological Studies ◽  
Surface Reactivity ◽  
Health Impacts ◽  
Adverse Health Effects ◽  
Particulate Air Pollution ◽  
Reactive Surface Area ◽  
Exact Relationship

With the rapid growth of nanotechnology and future bulk manufacture of nanomaterials comes the need to determine, understand and counteract any adverse health effects of these materials that may occur during manufacture, during use, or accidentally. Nanotechnology is expanding rapidly and will affect many aspects of everyday life; there are already hundreds of products that utilize nanoparticles. Paradoxically, the unique properties that are being exploited (e.g. high surface reactivity and ability to cross cell membranes) might have negative health impacts. The rapid progress in development and use of nanomaterials is not yet matched by toxicological investigations. Epidemiological studies implicate the ultrafine (nano-sized) fraction of particulate air pollution in the exacerbation of cardiorespiratory disease and increased morbidity. Experimental animal studies suggest that the increased concentration of nanoparticles and higher reactive surface area per unit mass, alongside unique chemistry and functionality, is important in the acute inflammatory and chronic response. Some animal models have shown that nanoparticles which are deposited in one organ (e.g. lung and gut) may access the vasculature and target other organs (e.g. brain and liver). The exact relationship between the physicochemistry of a nanoparticle, its cellular reactivity, and its biological and systemic consequences cannot be predicted. It is important to understand such relationships to enjoy the benefits of nanotechnology without being exposed to the hazards.

The epidemiology and possible mechanisms of disinfection by-products in drinking water

2009 ◽  
Vol 367 (1904) ◽  
pp. 4043-4076 ◽  
Author(s):  
Mark J. Nieuwenhuijsen ◽  
James Grellier ◽  
Rachel Smith ◽  
Nina Iszatt ◽  
James Bennett ◽  
...  
Keyword(s):  
Drinking Water ◽  
Health Effects ◽  
Semen Quality ◽  
Epidemiological Studies ◽  
Small Sample ◽  
Epidemiological Evidence ◽  
Adverse Health Effects ◽  
Adverse Health ◽  
Small Sample Sizes ◽  
By Products

This paper summarizes the epidemiological evidence for adverse health effects associated with disinfection by-products (DBPs) in drinking water and describes the potential mechanism of action. There appears to be good epidemiological evidence for a relationship between exposure to DBPs, as measured by trihalomethanes (THMs), in drinking water and bladder cancer, but the evidence for other cancers including colorectal cancer is inconclusive and inconsistent. There appears to be some evidence for an association between exposure to DBPs, specifically THMs, and little for gestational age/intrauterine growth retardation and, to a lesser extent, pre-term delivery, but evidence for relationships with other outcomes such as low birth weight, stillbirth, congenital anomalies and semen quality is inconclusive and inconsistent. Major limitations in exposure assessment, small sample sizes and potential biases may account for the inconclusive and inconsistent results in epidemiological studies. Moreover, most studies have focused on total THMs as the exposure metric, whereas other DBPs appear to be more toxic than the THMs, albeit generally occurring at lower levels in the water. The mechanisms through which DBPs may cause adverse health effects including cancer and adverse reproductive effects have not been well investigated. Several mechanisms have been suggested, including genotoxicity, oxidative stress, disruption of folate metabolism, disruption of the synthesis and/or secretion of placental syncytiotrophoblast-derived chorionic gonadotropin and lowering of testosterone levels, but further work is required in this area.

scholarly journals Airborne Aerosols and Human Health: Leapfrogging from Mass Concentration to Oxidative Potential

Atmosphere ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 917 ◽  
Author(s):  
Carolina Molina ◽  
Richard Toro A. ◽  
Carlos Manzano ◽  
Silvia Canepari ◽  
Lorenzo Massimi ◽  
...  
Keyword(s):  
Human Health ◽  
Health Effects ◽  
Mass Concentration ◽  
Complex Mixture ◽  
Epidemiological Studies ◽  
Atmospheric Particulate Matter ◽  
New Paradigm ◽  
Oxidative Potential ◽  
Adverse Health Effects ◽  
The Impact

The mass concentration of atmospheric particulate matter (PM) has been systematically used in epidemiological studies as an indicator of exposure to air pollutants, connecting PM concentrations with a wide variety of human health effects. However, these effects can be hardly explained by using one single parameter, especially because PM is formed by a complex mixture of chemicals. Current research has shown that many of these adverse health effects can be derived from the oxidative stress caused by the deposition of PM in the lungs. The oxidative potential (OP) of the PM, related to the presence of transition metals and organic compounds that can induce the production of reactive oxygen and nitrogen species (ROS/RNS), could be a parameter to evaluate these effects. Therefore, estimating the OP of atmospheric PM would allow us to evaluate and integrate the toxic potential of PM into a unique parameter, which is related to emission sources, size distribution and/or chemical composition. However, the association between PM and particle-induced toxicity is still largely unknown. In this commentary article, we analyze how this new paradigm could help to deal with some unanswered questions related to the impact of atmospheric PM over human health.

Sign in / Sign up

Export Citation Format

Share Document