Environmental Protection Agency Recommendations Research Articles

Association of community walkability and glycemic control among pregnant individuals with pregestational diabetes mellitus

Neighborhood walkability is a community-level social determinant of health that measures whether people who live in a neighborhood walk as a mode of transportation. Whether neighborhood walkability is associated with glycemic control among pregnant individuals with pregestational diabetes remains to be defined. This study aimed to evaluate the association between community-level neighborhood walkability and glycemic control as measured by hemoglobin A1c (A1C) among pregnant individuals with pregestational diabetes. This was a retrospective analysis of pregnant individuals with pregestational diabetes enrolled in an integrated prenatal and diabetes care program from 2012 to 2016. Participant addresses were geocoded and linked at the census-tract level. The exposure was community walkability, defined by the US Environmental Protection Agency National Walkability Index (score range 1-20), which incorporates intersection density (design), proximity to transit stops (distance), and a mix of employment and household types (diversity). Individuals from neighborhoods that were the most walkable (score, 15.26-20.0) were compared with those from neighborhoods that were less walkable (score <15.26), as defined per national Environmental Protection Agency recommendations. The outcomes were glycemic control, including A1C <6.0% and <6.5%, measured both in early and late pregnancy, and mean change in A1C across pregnancy. Modified Poisson regression and linear regression were used, respectively, and adjusted for maternal age, body mass index at delivery, parity, race and ethnicity as a social determinant of health, insurance status, baseline A1C, gestational age at A1C measurement in early and late pregnancy, and diabetes type. Among 417 pregnant individuals (33% type 1, 67% type 2 diabetes mellitus), 10% were living in the most walkable communities. All 417 individuals underwent A1C assessment in early pregnancy (median gestational age, 9.7 weeks; interquartile range, 7.4-14.1), and 376 underwent another A1C assessment in late pregnancy (median gestational age, 30.4 weeks; interquartile range, 27.8-33.6). Pregnant individuals living in the most walkable communities were more likely to have an A1C <6.0% in early pregnancy (15% vs 8%; adjusted relative risk, 1.46; 95% confidence interval, 1.00-2.16), and an A1C <6.5% in late pregnancy compared with those living in less walkable communities (13% vs 9%; adjusted relative risk, 1.33; 95% confidence interval, 1.08-1.63). For individuals living in the most walkable communities, the median A1C was 7.5 (interquartile range, 6.0-9.4) in early pregnancy and 5.9 (interquartile range, 5.4-6.4) in late pregnancy. For those living in less walkable communities, the median A1C was 7.3 (interquartile range, 6.2-9.2) in early pregnancy and 6.2 (interquartile range, 5.6-7.1) in late pregnancy. Change in A1C across pregnancy was not associated with walkability. Pregnant individuals with pregestational diabetes mellitus living in more walkable communities had better glycemic control in both early and late pregnancy. Whether community-level interventions to enhance neighborhood walkability can improve glycemic control in pregnancy requires further study.

Study of Efficiency and Reaction Rates Dechlorination of Nata De Coco Wastewater Using Sodium Thiosulfate

Chemical reduction with sodium thiosulfate is commonly used to dechlorinate chlorinated waste. U.S. Environmental Protection Agency recommends sodium thiosulfate (Na2S2O3) as a dechlorinating agent for waste samples containing residual chlorine before being released into the environment or entering the distribution system. However, sodium thiosulfate's efficiency and chlorination kinetics at different concentrations are still unknown due to a lack of information on chlorination kinetics. The study was conducted by determining the number of efficient doses of sodium thiosulfate and observing chlorination kinetics using sodium thiosulfate as a dechlorination agent observed at different stoichiometric ratios (1x, 1.5x, and 2x). Sodium thiosulfate at a stoichiometric dose of 2x can reduce chlorine residue by up to 0.4 ppm. The regression analysis of and constant rate are used in the kinetic analysis of sodium thiosulfate dechlorination processes. The kinetics of the chlorination process employing sodium thiosulfate is first order to the total concentration of chlorine in solution at a stoichiometric dosage of 2x, according to the findings.

An efficient 2-aminothiazolesalicylaldehyde fluorescent chemosensor for Fe2+ ion detection and a potential inhibitor of NUDT5 signaling hormone for breast cancer cell and molecular keypad lock application

A novel thiazole phenol conjugate, 2-aminothiazolesalicylaldehyde (receptor1) was designed and synthesized for the first time through a single step process via Schiff base condensation reaction. The formation of receptor1 was confirmed by FTIR, 13C NMR, and 1H NMR. The IR spectra confirmed the presence of the aldimine formation. It is further supported by the proton NMR, showing the disappearance of aldehyde peaks and the formation of a new imine peak. This is further corroborated by the 13C NMR. The receptor1 complexing with various metal ions were studied through fluorescence spectroscopy showed its selectivity toward Fe2+ ion following a reverse photoinduced electron transfer (PET) process compared to all other potentially competing ions. The receptor1 was applied as a sensor to sense Fe2+ ion in water samples. The detection limit for Fe2+ ion in drinking water was substantially lower (0.003 µM) than the EPA (environmental protection agency) recommendation (5.37 M). The capability of receptor1 in recovering Fe2+ ion in bore water, tap water, and drinking water was up to 99.5%. The receptor1 was also used as a chelating ligand (receptor1) in molecular docking and it was assessed as a potential inhibitor of NUDT5, a silence hormone signaling for breast cancer. The test compound (PDB: 5NWH) showed good affinity toward the target receptor1 with the binding energy of – 5.23 kcal mol−1. Furthermore, the receptor1 showed excellent reversibility property on adding EDTA solution. Due to the marvelous reversible property, a molecular-scale sequential information processing circuit is designed for the multi-task behavior such as ‘Writing-Reading-Erasing-Reading’ in the form of binary logic gate. The consecutive addition of Fe2+ ion and EDTA solution to receptor1 paves a way for the construction of INHIBIT logic gate. Additionally, the receptor1 showed the mimicking behavior of molecular keypad lock.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11696-022-02373-z.

A Study of Dispersed, Thermally Activated Limestone from Ukraine for the Safe Liming of Water Using ANN Models

Liming surface water is a fairly popular method of increasing the pH values and decreasing the concentration of phosphates and heavy metals. According to the Environmental Protection Agency (EPA) recommendations, the increase of water pH should not exceed 1.5. If surface water is the source of water supply, liming is a process that reduces water contamination. This should prevent the creation of an additional load for the water treatment plants in urban settlements. This article is an interdisciplinary research study aiming to (1) determine and compare the doses of new dispersed, thermally activated limestone and natural limestone, (2) find the relation between dose value and initial water parameters (pH, Eh and total mineralization), and (3) create an artificial neural network (ANN) model to predict changes in water pH values according to EPA recommendations. Recommended doses were obtained from experimental studies, and those of dispersed, thermally activated limestone were lower than the doses of natural limestone. Neural networks were used to predict the changes in water pH values when adding different doses of limestone with different initial water parameters using the ANN model. Four ANN models with different activation functions and loss function optimizers were tested. The best results were obtained for the network with the ReLU activation function for hidden layers of neurons and Adam’s loss function optimizer (MAPE = 14.1%; R2 = 0.847). Further comparison of the results of the loss function and the results of calculating the quality metric for the training and validation dataset has shown that the created ANN can be used to solve the set research issue.

General Overview of Radon Studies in Health Hazard Perspectives.

The adverse human health effects due to ionizing radiation are well known. Radon is the major source of background radiation among those that are of natural origin. It contributes about 55% of the natural radiation dose to humans. It is a colorless, odorless, and tasteless radioactive noble gas that comes from the natural radioactive decay series of uranium. Radon can be found everywhere in the atmosphere and become attached to aerosols in the air. The aerosols carrying radon and its progeny can be inhaled and deposited in different regions of the human respiratory tract. The deposited radioactive aerosols continue to decay and exposing the lung to ionizing radiation can destroy sensitive cells in the lung, causing a mutation that turns to be cancerous. Different countries and international and national organizations put their action levels to reduce radon lung cancer risk. The Environmental Protection Agency recommends 148 Bq/m3 as the action level. On the other hand, International Commission for Radiation Protection (ICRP) recommends 200 Bq/m3 as the action level. The main objective of this review is to focus on how radon is established as a health hazard, ways of radon detection and measurements, methods of reducing and controlling high indoor radon concentration, and what are the recommended international action levels of radon concentrations. It mainly focuses on the health perspective of radon studies because it is now a crucial and hot issue in the world. In most developing countries like our country Ethiopia, radon studies are not well investigated.

Vapor intrusion risk evaluation using automated continuous chemical and physical parameter monitoring

AbstractVapor intrusion risk characterization efforts are challenging due to complexities associated with background indoor air constituents, preferential subsurface migration pathways, and representativeness limitations associated with traditional randomly timed time‐integrated sampling methods that do not sufficiently account for factors controlling concentration dynamics. The U.S. Environmental Protection Agency recommends basing risk related decisions on the reasonable maximum exposure (RME). However, with very few exceptions, practitioners have not been applying this criterion. The RME will most likely occur during upward advective flux conditions. As such, for RME determinations, it is important to sample when upward advective flux conditions are occurring. The most common vapor intrusion assessment efforts include randomly timed sample collection events, and therefore do not accurately yield RME estimates. More specifically, researchers have demonstrated that randomly timed sampling schemes can result in false negative determinations of potential risk corresponding to RMEs. For sites experiencing trichloroethylene (TCE) vapor intrusion, the potential for acute risks poses additional challenges, as there is a critical need for rapid response to exposure exceedances to minimize health risks and liabilities. To address these challenges, continuous monitoring platforms have been deployed to monitor indoor concentrations of key volatile constituents, atmospheric pressure, and pressure differential conditions that can result in upward toxic vapor transport and entry into overlying buildings. This article demonstrates how vapor intrusion RME‐based risks can be successfully and efficiently determined using continuous monitoring of concentration and parameters indicating upward advective chemical flux. Time series analyses from multiple selected 8‐ and 24‐hr time increments during upward advective TCE flux conditions were performed to simulate results expected from the most commonly employed sampling methods. These analyses indicate that, although most of the selected time increments overlap within the same 24‐hr window, results and conclusions vary. As such, these findings demonstrate that continuous monitoring of concentration and parameters such as differential pressure and determination of a time‐weighted concentration average over a selected duration when upward advective flux is occurring can allow for a realistic RME‐based risk estimate.

Public health effects due to insufficient groundwater quality monitoring in Igando and Agbowo regions in Nigeria: A review

This paper emphasizes the need for monitoring groundwater resources by analyzing the health implications of inadequate monitoring. It highlights the importance of groundwater quality monitoring in Nigeria—a country where population dependence on groundwater is 60%. The effects of Soluos dumpsite leachate in Igando, Lagos–Nigeria, and septic tank seepages in Agbowo, Ibadan–Nigeria on groundwater quality are analyzed. All samples used in this study appeared to be microbially contaminated. This is linked to too close distances [< 50 ft (15.24 m) the United States Environmental Protection Agency recommendation] between septic tanks and groundwater wells, as well as non-engineered dumpsites used for waste disposal. This shows that groundwater within the study area is unsafe for drinking purposes. Even with the clayey soil stratigraphy of the study area which is believed to influence the natural attenuation of leachate into groundwater, high concentrations of lead (Pb) and manganese (Mn) were seen in some locations around the dumpsite. The study points to the inherent cost for individuals and government due to insufficient groundwater quality which could have been otherwise avoided through groundwater monitoring and proper waste management. This review accentuates the need for improved water quality towards achieving SDG 6.1 (universal and equitable access to safe drinking water) and SDG 3 (Good health and well-being) in Nigeria.

Focus on Chronic Exposure for Deriving Drinking Water Guidance Underestimates Potential Risk to Infants.

In 2007, the Minnesota Department of Health (MDH) developed new risk assessment methods for deriving human health-based water guidance (HBG) that incorporated the assessment of multiple exposure durations and life stages. The methodology is based on US Environmental Protection Agency recommendations for protecting children’s health (US EPA 2002). Over the last 10 years, the MDH has derived multiple duration (e.g., short-term, subchronic, and chronic) water guidance for over 60 chemicals. This effort involved derivation of multiple duration reference doses (RfDs) and selection of corresponding water intake rates (e.g., infant, child, and lifetime). As expected, RfDs typically decreased with increasing exposure duration. However, the corresponding HBG frequently did not decrease with increasing duration. For more than half of the chemicals, the shorter duration HBG was lower than chronic HBG value. Conventional wisdom has been that chronic-based values will be the most conservative and will therefore be protective of less than chronic exposures. However, the MDH’s experience highlights the importance of evaluating short-term exposures. For many chemicals, elevated intake rates early in life, coupled with short-term RfDs, resulted in the lowest HBG. Drinking water criteria based on chronic assessments may not be protective of short-term exposures in highly exposed populations such as formula-fed infants.

Children's Hair Mercury Concentrations and Seafood Consumption in Five Regions of Japan.

Exposure to methylmercury (MeHg) during the foetal and postnatal periods is known to have adverse effects on children's development. However, little attention has been paid to MeHg exposure during early childhood in Japan. To examine the regional differences in MeHg exposure and seafood consumption and the association between MeHg exposure and seafood consumption and dental metal restorations, we measured the total mercury (T-Hg) concentration in hair as an MeHg exposure index, and using questionnaires, we measured the frequency and amount of seafood consumption and the presence of dental metal restorations in 118 children aged 3-6years in five regions of Japan. The arithmetic and geometric means of the T-Hg concentrations in hair were 1.03 and 0.87ppm, respectively, and approximately 40% of the children exceeded the United States Environmental Protection Agency recommendation of 1.0ppm. Significant regional differences in the hair T-Hg concentrations were found among the five regions, and the regional differences were consistent with the traditional regional patterns of eating fatty fish. According to the regression analysis, the consumption of fatty fish, particularly tuna/swordfish, had a significant effect on hair T-Hg concentrations, whereas age, sex, the materials used for dental metal restorations, and other types of seafood or fish/shellfish had no significant effects.

Identifying Optimal Multi-state collaborations for reducing CO2 emissions by co-firing biomass in coal-burning power plants

The US Environmental Protection Agency (EPA) has recently proposed a rule that aims to reduce carbon emissions from US coal-fired power plants. The proposed “Clean Power Plan” specifies state-specific rate-based goals to achieve a total US carbon emission reduction of 32% below 2005 levels by 2030. An increase in the co-firing of woody biomass with coal to generate biopower is one of the potential approaches that electricity providers could take to comply with EPA’s proposed rules. We develop a mixed integer linear programming (MILP) model to identify minimum-cost approaches for reducing CO2 emissions via co-firing biomass subject to spatially-explicit biomass availability constraints. An important feature of the EPA recommendations is an allowance for states to participate in multi-state compliance strategies. We extend the MILP model to optimize within a larger geographical framework that allows states to identify minimum-cost partnerships that meet aggregated emission reduction goals. We apply the MILP model to data for five Midwestern US states to determine the role that co-firing biomass could play in achieving their EPA-proposed emission reduction targets, and find that some states can meet their renewable energy generation targets through co-firing, although co-firing alone is not sufficient to achieve any state’s emission reduction targets.

Disparity between state fish consumption advisory systems for methylmercury and US Environmental Protection Agency recommendations: A case study of the south central United States

Fish consumption advisories are used to inform citizens in the United States about noncommercial game fish with hazardous levels of methylmercury (MeHg). The US Environmental Protection Agency (USEPA) suggests issuing a fish consumption advisory when concentrations of MeHg in fish exceed a human health screening value of 300 ng/g. However, states have authority to develop their own systems for issuing fish consumption advisories for MeHg. Five states in the south central United States (Arkansas, Louisiana, Mississippi, Oklahoma, and Texas) issue advisories for the general human population when concentrations of MeHg exceed 700 ng/g to 1000 ng/g. The objective of the present study was to estimate the increase in fish consumption advisories that would occur if these states followed USEPA recommendations. The authors used the National Descriptive Model of Mercury in Fish to estimate the mercury concentrations in 5 size categories of largemouth bass-equivalent fish at 766 lentic and lotic sites within the 5 states. The authors found that states in this region have not issued site-specific fish consumption advisories for most of the water bodies that would have such advisories if USEPA recommendations were followed. One outcome of the present study may be to stimulate discussion between scientists and policy makers at the federal and state levels about appropriate screening values to protect the public from the health hazards of consuming MeHg-contaminated game fish.

The Emperor's Old Clothes: An Inconvenient Truth About Currently Accepted Vapor Intrusion Assessment Methods

The Emperor's Old Clothes: An Inconvenient Truth About Currently Accepted Vapor Intrusion Assessment Methods

Highly Selective and Sensitive Luminescence Turn-On-Based Sensing of Al(3+) Ions in Aqueous Medium Using a MOF with Free Functional Sites.

A new metal-organic framework [Co(OBA)(DATZ)0.5(H2O)] {OBA = 4,4'-oxybis(benzoic acid) and DATZ = 3,5-diamino-1,2,4-triazole}, 1, was synthesized by hydrothermal reaction. Single-crystal X-ray data of 1 confirmed two-dimensional rhombus grid network topology with a free nitrogen site of triazole ring and two amine groups of each DATZ. Photoluminescence study of 1 in aqueous medium shows blue emission at 407 nm upon excitation at 283 nm. This emissive property was used for the sensing of Al(3+) ions in aqueous medium through very high luminescence turn-on (6.3-fold) along with the blue shifting (∼24 nm) of the emission peak. However, luminescence studies in the presence of other common metal ions such as Mg(2+), Zn(2+), Ni(2+), Co(2+), Mn(2+), K(+), Na(+), Ca(2+), Cd(2+), Hg(2+), Cu(2+), Fe(2+), Fe(3+), and Cr(3+) in aqueous medium shows luminescence quenching in varying extent. Interestingly, the luminescence turn-on-based selectivity of Al(3+) ions in aqueous medium was achieved even in the presence of the highest quenchable metal ion, Fe(3+). Furthermore, very high sensitivity was observed in the case of Al(3+) ions with a limit of detection of Al(3+) of 57.5 ppb, which is significantly lower than the higher limit of U.S. Environmental Protection Agency recommendation of Al(3+) ion for drinking water (200 ppb).

Exposure profiles of mercury in human hair at a terai belt of North India.

Human hair is frequently used as a bioindicator of mercury exposure. Mercury (Hg) has for centuries been a useful metal in a variety of applications. Unfortunately, this usefulness is counterbalanced by its neurotoxicological health impact. The US Environmental Protection Agency recommends keeping the hair Hg level <1.0µg/g. Therefore, an investigation has been performed in order to ascertain the hair Hg levels among the people living at the terai belt of North India. Hair samples were collected from 111 individuals and were placed in an identified plastic bag, stapled to prevent the shift of the hair strand. Samples were analyzed by combustion, gold amalgamation, atomic absorption spectrometry (C-GA-AAS). The mean Hg level in hair was 0.28µg/g for the whole group ranging from 0.0012 to 1.9091µg/g. The mean hair Hg levels were 0.16µg/g for men and 0.12µg/g for women, indicating that men had higher hair Hg levels than women. Total hair Hg was found to be significantly associated with age, gender and fish consumption frequency. 98% of the total sample had hair Hg concentrations less than 1.0µg/g, i.e, within safe dose, whereas only 2% had Hg concentrations greater than 1.0µg/g, thereby exceeding the safe dose.

Developing a laddered algorithm for the management of intractable epistaxis: a risk analysis.

For patients with epistaxis in whom initial interventions, such as anterior packing and cauterization, had failed, options including prolonged posterior packing, transnasal endoscopic sphenopalatine artery ligation (TESPAL), and embolization are available. However, it is unclear which interventions should be attempted and in which order. While cost-effectiveness analyses have suggested that TESPAL is the most responsible use of health care resources, physicians must also consider patient risk to maintain a patient-centered decision-making process. To quantify the risk associated with the management of intractable epistaxis. A risk analysis was performed using literature-reported probabilities of treatment failure and adverse event likelihoods in an emergency department and otolaryngology hospital admissions setting. The literature search included articles from 1980 to May 2014. The analysis was modeled for a 50-year-old man with no other medical comorbidities. Severities of complications were modeled based on Environmental Protection Agency recommendations, and health state utilities were monetized based on a willingness to pay $22 500 per quality-adjusted life-year. Six management strategies were developed using posterior packing, TESPAL, and embolization in various sequences (P, T, and E, respectively). Total risk associated with each algorithm quantified in US dollars. Algorithms involving posterior packing and TESPAL as first-line interventions were found to be similarly low risk. The lowest-risk approaches were P-T-E ($2437.99 [range, $1482.83-$6976.40]), T-P-E ($2840.65 [range, $1136.89-$8604.97]), and T-E-P ($2867.82 [range, $1141.05-$9833.96]). Embolization as a first-line treatment raised the total risk significantly owing to the risk of cerebrovascular events (E-T-P, $11 945.42 [range, $3911.43-$31 847.00]; and E-P-T, $11 945.71 [range, $3919.91-$31 767.66]). Laddered approaches using TESPAL and posterior packing appear to provide the lowest risk. Combining risk and cost-effectiveness perspectives, we recommend a laddered approach to intractable epistaxis with TESPAL first, followed by either embolization or posterior packing.

Forced solid-state interactions for the selective "turn-on" fluorescence sensing of aluminum ions in water using a sensory polymer substrate.

Selective and sensitive solid sensory substrates for detecting Al(III) in pure water are reported. The material is a flexible polymer film that can be handled and exhibits gel behavior and membrane performance. The film features a chemically anchored salicylaldehyde benzoylhydrazone derivative as an aluminum ion fluorescence sensor. A novel procedure for measuring Al(III) at the ppb level using a single solution drop in 20 min was developed. In this procedure, a drop was allowed to enter the hydrophilic material for 15 min before a 5 min drying period. The process forced the Al(III) to interact with the sensory motifs within the membrane before measuring the fluorescence of the system. The limit of detection of Al(III) was 22 ppm. Furthermore, a water-soluble sensory polymer containing the same sensory motifs was developed with a limit of detection of Al(III) of 1.5 ppb, which was significantly lower than the Environmental Protection Agency recommendations for drinking water.

Emergency Water Treatment with Bleach in the United States: The Need to Revise EPA Recommendations

During emergencies in the United States, the Environmental Protection Agency (EPA) currently recommends using bottled water, or boiling or treating water by adding 1/8 teaspoon (or 8 drops) of bleach to 1 gal of water. This bleach recommendation is internally inconsistent, a relatively high chlorine dose (5.55-8.67 mg/L), and unsupported by evidence. In this study, bleach was added in three different dosages to six waters available to emergency-affected populations in each of six states; free chlorine residual (FCR) and Escherichia coli/total coliforms were measured 1-24 h after treatment. Data were analyzed using four efficacy criteria. Results indicated the dosages in the current EPA recommendation are unnecessarily high to ensure (1) maintenance of FCR for 24 h after treatment, (2) absence of E. coli/total coliforms, and (3) establishment of a CT-factor sufficient to inactivate Giardia lamblia and enteric viruses 1 h after treatment. Additionally, emergency-prone populations did not have the materials to complete treatment with bleach in their household. Therefore, we recommend EPA review and revise the current recommendation to establish an internally consistent, criteria-based recommendation that is usable by emergency-affected populations. We also recommend investigating the use of new or commercially available water treatment products for emergency response in the United States.

INFORMATION AND THE DEMAND FOR CLEAN AIR

I. INTRODUCTION The idea that household location decisions are influenced by neighborhood characteristics is well established empirically. A number of studies have identified local air quality as a specific neighborhood-level determinant (Bayer. Keohane, and Timmins 2009;. Finney, Goetzke. and Yoon 2011; Kahn 2000; Zabel and Kiel 2000). The findings on air quality suggest that households are able to access and react to information on the environmental good in making location decisions. The average effects air quality has on location, however, may mask substantial variation in response to the amenity across households, many of which may not recognize the good at all. This paper examines the relationship between the household's sensitivity to local environmental quality and its exposure to information on the environment. Households may acquire information on the environment from multiple sources, including personal experience (e.g.. visual observation of smog), informal communication with neighbors, and government pronouncements. A large part of the primary data on air quality in the United States comes from air monitoring stations operated by state governments and the Environmental Protection Agency (EPA). This study estimates the location determinants of a sample of households relocating within California, a state with long-established public information programs on environmental quality. In California, air quality .alerts have served as an important medium conveying information on environmental quality to state residents. The alerts. which normally include information on the possible health effects of poor air quality, occur primarily in urban areas, whose air pollution levels are normally higher than in nonurban areas. Exposure to the alerts could increase household sensitivity to the environment in making location decisions. This study finds evidence of this effect for the sample of California households. II. AIR QUALITY AND PUBLIC INFORMATION PROGRAMS The primary tool local governments use to relay information on the environment is the Air Quality Index (AQI), a measure developed by the EPA. The index ranges from 0 to 500, where under 100 is considered good-to-moderate air quality; 100 to 150 is determined by the EPA unhealthy at least for sensitive groups; and a score over 150 is considered generally unhealthy and comes with an EPA recommendation that those with respiratory .ailments avoid prolonged outdoor exposure and everyone else limit exposure. The EPA previously used the Pollution Standard Index (PSI), replacing it with the AQI in 2000. The two indices are closely related., the AQI modifies the standard used in the PSI for particulate matter and ozone, two of the five pollutants that make up the indices. Ground-level ozone, formed from a chemical reaction of pollutants in the lower atmosphere, is a significant environmental problem specifically in urban areas (1) Exposure to high ozone levels affects lung function; its immediate effects are more serious for those with respiratory diseases, such as asthma. California is one of the few states whose air quality standards are more stringent than federal standards under the Clean Air Act. The state grades the air of every county, determining yearly each county's compliance with state standards for various pollutants. The state's current ozone thresholds are an 8-h average of 0.070 parts per million (ppm), and a 1-h mean of 0.090 ppm; the EPA's current ozone standard is an 8-h average of 0.075 ppm. Yearly, the majority of counties fail state standards; the attainment counties in the state are mainly in nonurban areas. (2) Polluting facilities in non-attainment areas are subject to increased state regulation. The state assigns 35 local governments the task of controlling local air pollution. (3) The districts are the primary source of official state information on local environmental quality, including the dissemination of air quality alerts. …

Meeting the Needs of the People: Fish Consumption Rates in the Pacific Northwest

Meeting the Needs of the People: Fish Consumption Rates in the Pacific Northwest

The Green Heart Initiative

The Green Heart Initiative