Photochemical assessment monitoring stations program adapted for ozone precursors monitoring network in Mexico City

Atmósfera ◽  
2016 ◽  
Vol 29 (2) ◽  
pp. 169 ◽  
Author(s):  
Mónica Del Carmen Jaimes Palomera ◽  
Humberto Bravo Álvarez ◽  
Rodolfo Sosa Echeverria ◽  
Elías Granados Hernández ◽  
Pablo Sánchez Álvarez ◽  
...  
Keyword(s):  
Mexico City ◽  
Atmospheric Chemistry ◽  
Control Strategies ◽  
Monitoring Network ◽  
Ozone Precursors ◽  
The Us ◽  
Us Epa ◽  
Photochemical Modeling ◽  
Urban Ozone ◽  
Monitoring Stations

The purpose of this study is to select a number of stations from the existing Sistema de Monitoreo Atmosférico (Atmospheric Monitoring System, SIMAT) of Mexico City to serve as an equivalent to the Photochemical Assessment Monitoring Stations according to the US-EPA criteria, in order to improve the study of urban ozone occurrence. The results indicate that four existing SIMAT stations meet the criteria to form such network. The relevance of this study is to present an ozone precursors monitoring network with continuous measurements for future trustful studies on air quality for ozone, considering the atmospheric chemistry and photochemical modeling for the design control strategies appropriate for the particular conditions of Mexico City.

scholarly journals Impact of primary formaldehyde on air pollution in the Mexico City Metropolitan Area

2008 ◽  
Vol 8 (6) ◽  
pp. 19605-19635 ◽  
Author(s):  
W. Lei ◽  
M. Zavala ◽  
B. de Foy ◽  
R. Volkamer ◽  
M. J. Molina ◽  
...  
Keyword(s):  
Mexico City ◽  
Metropolitan Area ◽  
Atmospheric Chemistry ◽  
Transport Model ◽  
Monitoring Network ◽  
Ambient Air ◽  
Urban Atmosphere ◽  
Chemical Transport Model ◽  
Early Afternoon ◽  
The Impact

Abstract. Formaldehyde (HCHO) is a radical source that plays an important role in urban atmospheric chemistry and ozone formation. The Mexico City Metropolitan Area (MCMA) is characterized by high anthropogenic emissions of HCHO (primary HCHO), which together with photochemical production of HCHO from hydrocarbon oxidation (secondary HCHO), lead to high ambient HCHO levels. The CAMx chemical transport model was employed to evaluate the impact of primary HCHO on its ambient concentration, on the ROx radical budget, and on ozone (O3) formation in the MCMA. Important radical sources, including HCHO, HONO, and O3-olefin reactions, were constrained by measurements from routine observations of the local ambient air monitoring network and the MCMA-2003 field campaign. Primary HCHO was found not only contributing significantly to the ambient HCHO concentration, but also enhancing the radical budget and O3 production in the urban atmosphere of the MCMA. Overall in the urban area, total daytime radical production is enhanced by up to 10% and peak O3 concentration by up to 8%. While primary HCHO contributes predominantly to the ambient HCHO concentration between nighttime and morning rush hours, significant influence on the radical budget and O3 production starts early morning, culminates at mid-morning and is sustained until early afternoon.

Fundamental Characterisation of Dredged Marine Sediments from Kuala Perlis Jetty by XRF, XRD and FTIR

2012 ◽  
Vol 620 ◽  
pp. 469-473 ◽  
Author(s):  
Norhashimah Ramli ◽  
Mohammad Hafizuddin Haji Jumali ◽  
Wan Safizah Wan Salim
Keyword(s):  
Heavy Metals ◽  
Marine Sediments ◽  
Xrd Analysis ◽  
Raw Material ◽  
Ftir Analysis ◽  
Huge Amount ◽  
The Us ◽  
Dredged Marine Sediment ◽  
Primary Mineral ◽  
Us Epa

Dredging along Kuala Perlis Jetty results in huge amount of marine sediments which has thrown considerable challenge for disposal. This research was conducted to characterize dredged marine sediment which was collected at Kuala Perlis Jetty as potential raw material for brick production. Three different characterizations were performed namely XRF, XRD and FTIR. XRF analysis showed the presence of SiO2 and Al2O3 as major quantities. Low concentration of heavy metals namely As, Cr, Cu, Pb, Ni and Zn presence in the sediment comply the US EPA guideline for brick production. XRD analysis indicated the presence of quartz as primary mineral while kaolinite and illite also present as secondary and ternary phases. FTIR analysis identified various form of minerals presence in the samples which strongly supported XRD results.

A review on bromate occurrence and removal strategies in water supply

2006 ◽  
Vol 6 (6) ◽  
pp. 131-136 ◽  
Author(s):  
L. Xie ◽  
C. Shang
Keyword(s):  
Water Supply ◽  
Control Strategies ◽  
Well Being ◽  
Potential Health ◽  
Drinking Water Standard ◽  
Carbon Adsorption ◽  
The Us ◽  
Current Maximum ◽  
Ammonia Addition ◽  
Removal Technologies

The need of disinfecting potable water to eliminate potential health risks associated with waterborne pathogens, however inevitably resulting in leaving elevated toxicity in water by forming disinfection by-products (DBPs) is being considered as one of the primary threats to human well-being. Bromate is a carcinogenic DBP mainly formed during ozonation of bromide-containing water. The current maximum contaminant level (MCL) of bromate in the US national primary drinking water standard is set at 10 μg/L. With continuous improvements in analytical instrumentation and removal technologies, a lower MCL for bromate is expected in the future. Current researches on bromate control strategies involve minimizing bromate formation (like ammonia addition) or removing bromate after formation (like carbon adsorption), however have their own limitations. Seeking for alternative bromate control strategies that can be used alone (or in combine with others) is of great value and in urgent need when water quality standards are getting more stringent. This paper reviews the occurrence of bromate in water supply and evaluates the effectiveness of bromate removal technologies applied, to advance our understanding of bromate fate and degradation in water supply system for future study.

scholarly journals Indoor thermal factors and symptoms in office workers: findings from the US EPA BASE study

Indoor Air ◽  
2009 ◽  
Vol 19 (4) ◽  
pp. 291-302 ◽  
Author(s):  
M. J. Mendell ◽  
A. G. Mirer
Keyword(s):  
Office Workers ◽  
Base Study ◽  
The Us ◽  
Us Epa

Back to the Future: Reducing Atmospheric Particulate Matter Levels to Improve Human Health

2021 ◽  
Author(s):  
Spyros Pandis
Keyword(s):  
Particulate Matter ◽  
Atmospheric Aerosols ◽  
Atmospheric Chemistry ◽  
Control Strategy ◽  
Atmospheric Particulate Matter ◽  
Anthropogenic Emissions ◽  
The Us ◽  
Negative Impacts ◽  
Predictive Understanding ◽  
Physical And Chemical

<p>The human development of our planet has a variety of negative impacts on the composition of its atmosphere at every scale – locally, regionally, and even globally. One of these dramatic changes has been the increase in the mass concentrations of sub-micrometer particles by one to sometimes two orders of magnitude over populated areas in the Northern Hemisphere. These atmospheric aerosols can cause serious health problems, reduce visibility, contribute to acidic deposition and material damage, but are also cooling the planet by reflecting sunlight back to space. Atmospheric chemistry occurs within a fabric of complicated atmospheric dynamics and physics. This interplay often results in nonlinear and often counterintuitive changes of the system when anthropogenic emissions change. A major goal of our research has been to gain a predictive understanding of the physical and chemical processes that govern the dynamics, size, and chemical composition of atmospheric aerosols.</p><p>To illustrate the advances in the experimental techniques and theoretical tools in atmospheric aerosol science, we will go back to the beginning of the 21<sup>st</sup> century and we will revisit the design a particulate matter control strategy for the Eastern US based on the data, knowledge, and tools available at that time. We will then look at the effects of the parts of this control strategy that have been materialized and their effects on public health using the current understanding. Finally, we will look forward in ways of further improving air quality in the US and Europe.</p>

scholarly journals Aspiration in injections: should we continue or abandon the practice?

F1000Research ◽  
2017 ◽  
Vol 3 ◽  
pp. 157
Author(s):  
Yasir Sepah ◽  
Lubna Samad ◽  
Arshad Altaf ◽  
Muhammad Sohail Halim ◽  
Nithya Rajagopalan ◽  
...  
Keyword(s):  
Medical Association ◽  
Simple Procedure ◽  
Health Agency ◽  
Monitoring Network ◽  
Nursing Schools ◽  
Global Network ◽  
World Health ◽  
Sources Of Information ◽  
Starting Point ◽  
The Us

Aspiration during any kind of injection is meant to ensure that the needle tip is at the desired location during this blind procedure. While aspiration appears to be a simple procedure, it has generated a lot of controversy concerning the perceived benefits and indications. Advocates and opponents of aspiration both make logically sound claims. However, due to scarcity of available data, there is no evidence that this procedure is truly beneficial or unwarranted. Keeping in view the huge number of injections given worldwide, it is important that we draw attention to key questions regarding aspiration that, up till now, remain unanswered. In this review, we have attempted to gather and present literature on aspiration both from published and non-published sources in order to provide not only an exhaustive review of the subject, but also a starting point for further studies on more specific areas requiring clarification. A literature review was conducted using the US National Institute of Health’s PubMed service (including Medline), Google Scholar and Scopus. Guidelines provided by the World Health Organization, Safe Injection Global Network, International Council of Nursing, Center for Disease Control, US Federal Drug Agency, UK National Health Services, British Medical Association, Europe Nursing and Midwifery Council, Public Health Agency Canada, Pakistan Medical Association and International Organization of Standardization recommendations 7886 parts 1-4 for sterile hypodermics were reviewed for relevant information. In addition, curricula of several medical/nursing schools from India, Nigeria and Pakistan, the US pharmacopeia Data from the WHO Program for International Drug Monitoring network in regard to adverse events as a result of not aspirating prior to injection delivery were reviewed. Curricula of selected major medical/nursing schools in India, Nigeria and Pakistan, national therapeutic formularies, product inserts of most commonly used drugs and other possible sources of information regarding aspiration and injections were consulted as well.

Water reclamation and reuse criteria in the U.S.

1996 ◽  
Vol 33 (10-11) ◽  
pp. 451-462 ◽  
Author(s):  
James Crook ◽  
Rao Y. Surampalli
Keyword(s):  
Surface Waters ◽  
Water Reuse ◽  
Reclaimed Water ◽  
Water Reclamation ◽  
Water Supplies ◽  
The Us ◽  
Attractive Option ◽  
Us Epa ◽  
The Individual ◽  
The U.S

Increasing demands on water resources for domestic, commercial, industrial, and agricultural purposes have made water reclamation and reuse an attractive option for conserving and extending available water supplies. Also, many water reuse projects are implemented to eliminate a source of contamination in surface waters or as a least-cost alternative to meeting stringent discharge requirements. Reclaimed water applications range from pasture irrigation to augmentation of potable water supplies. Water reclamation and reuse criteria are principally directed at health protection. There are no federal regulations governing water reuse in the U.S.; hence, the regulatory burden rests with the individual states. This has resulted in differing standards among states that have developed criteria. This paper summarizes and compares the criteria from some states that have developed comprehensive regulations. Guidelines published by the US. EPA and the rationale behind them are presented for numerous types of reclaimed water applications.

scholarly journals How alkaline compounds control atmospheric aerosol particle acidity

2021 ◽  
Vol 21 (19) ◽  
pp. 14983-15001
Author(s):  
Vlassis A. Karydis ◽  
Alexandra P. Tsimpidi ◽  
Andrea Pozzer ◽  
Jos Lelieveld
Keyword(s):  
Public Health ◽  
Aerosol Particle ◽  
Atmospheric Chemistry ◽  
Climate Model ◽  
Control Strategies ◽  
Atmospheric Particulate Matter ◽  
Cloud Formation ◽  
Mass Composition ◽  
The Past ◽  
Aerosol Hygroscopicity

Abstract. The acidity of atmospheric particulate matter regulates its mass, composition, and toxicity and has important consequences for public health, ecosystems and climate. Despite these broad impacts, the global distribution and evolution of aerosol particle acidity are unknown. We used the comprehensive atmospheric multiphase chemistry–climate model EMAC (ECHAM5/MESSy Atmospheric Chemistry) to investigate the main factors that control aerosol particle acidity and uncovered remarkable variability and unexpected trends during the past 50 years in different parts of the world. Aerosol particle acidity decreased strongly over Europe and North America during the past decades while at the same time it increased over Asia. Our simulations revealed that these particle acidity trends are strongly related to changes in the phase partitioning of nitric acid, production of sulfate in aqueous aerosols, and the aerosol hygroscopicity. It is remarkable that the aerosol hygroscopicity (κ) has increased in many regions following the particle pH. Overall, we find that alkaline compounds, notably ammonium and to a lesser extent crustal cations, regulate the particle pH on a global scale. Given the importance of aerosol particles for the atmospheric energy budget, cloud formation, pollutant deposition, and public health, alkaline species hold the key to control strategies for air quality and climate change.

Sign in / Sign up

Export Citation Format

Share Document