Environmental chemistry

Ozone (), also called trioxygen, is an inorganic molecule with the chemical formula ''''''. It is a pale-blue gas with a distinctively pungent odour. It is an allotrope of oxygen that is much less stable than the diatomic allotrope , breaking down in the lower atmosphere to (dioxygen). Ozone is formed from dioxygen by the action of ultraviolet (UV) light and electrical discharges within the Earth's atmosphere. It is present in very low concentrations throughout the atmosphere, with its highest concentration high in the ozone layer of the stratosphere, which absorbs most of the Sun's ultraviole

rain that is unusually acidic

Cyanobacteria ( ) are a group of autotrophic gram-negative bacteria of the phylum Cyanobacteriota that can obtain biological energy via oxygenic photosynthesis. Cyanobacteria apparently originated in a freshwater or terrestrial environment, and first appeared in the middle Archean eon. They are probably the most numerous taxon to have ever existed on Earth. The name "cyanobacteria" () refers to their bluish green (cyan) color, which forms the basis of cyanobacteria's informal common name, blue-green algae.

atom, molecule, or ion that has an unpaired valence electron; typically highly reactive

pollution of land by human-made chemicals or other alteration

thumb|313x313px|Eutrophication can cause harmful algal blooms like this one in a river near Chengdu, China.

scientific study of the chemical and biochemical phenomena that occur in natural places

flow of excess rainwater not infiltrating in the ground over its surface

thumb|Sawdust made with hand saw thumb|:ja:オガ炭|Ogatan, Japanese [[charcoal briquettes made from sawdust]] thumb|Sawdust vendors in Kashgar markets

area of chemistry and chemical engineering focused on minimizing hazardous substances

branch of atmospheric science

The Restriction of Hazardous Substances Directive 2002/95/EC (RoHS 1), short for Directive on the restriction of the use of certain hazardous substances in electrical and electronic equipment, was adopted in February 2003 by the European Union.

measure of the amount of oxygen that can be consumed by reactions in a solution

thumb|281x281px|Defoliants are used as an aid in the harvesting of certain crops such as cotton. thumb|2,4-D, one of the first chemical herbicides used as a defoliant.|281x281px thumb|U.S. Army Huey helicopter spraying [[Agent Orange over agricultural land during the Vietnam War.|283x283px]]

radical composed by one atom of oxygen and one atom of hydrogen

intervals in the Earth's past

set of pseudo units to describe small values of miscellaneous dimensionless quantities

measurement in environmental chemistry

thumb|The Passaic Agricultural Chemical Works in Newark, New Jersey, 1876 An agrochemical or agrichemical, a contraction of agricultural chemical, is a chemical product used in conventional or industrial agriculture. Agrochemical typically refers to pesticides and synthetic fertilizers. The term agrochemical is sometimes used informally synonymously with pesticides, sometimes also informally to mean pesticides and fertilizers, and sometimes more correctly to include all chemicals used in agriculture. Other chemicals used in agriculture are plant hormones and plant growth regulators (PGRs), ins

measure of soil chemistry

Strongly oxidizing solution of hydrogen peroxide mixed with dissolved iron as catalyst

thumb|In the experiment above, photons from a light source (out of frame on the right hand side) are absorbed by the surface of the titanium dioxide () disc, exciting electrons within the material. These then react with the water molecules, splitting it into its constituents of hydrogen and oxygen. In this experiment, chemicals dissolved in the water prevent the formation of oxygen, which would otherwise recombine with the hydrogen.

thumb|300px|Lake Erie in October 2011, during an intense cyanobacteria bloom

substance within a material differing from its overall composition

In analytical chemistry, biomonitoring is the measurement of the body burden of toxic chemical compounds, elements, or their metabolites, in biological substances. Often, these measurements are done in blood and urine. Biomonitoring is performed in both environmental health, and in occupational safety and health as a means of exposure assessment and workplace health surveillance.

The bisphenols () are a group of industrial chemical compounds related to diphenylmethane; commonly used in the production of plastics and epoxy resins. They feature two hydroxyphenyl groups linked by a methylene bridge. Also included are bisphenol S, P, and M. "Bisphenol" is a common name; the letter following denotes the variant, which depends on the additional substituents. Bisphenol A is the most common representative of the group, with millions of metric tons produced globally in the past decade, often simply called "bisphenol".

thumb|A plastic bucket used as an open-air flowerpot photodegraded after some years. Photodegradation is the alteration of materials by light. Commonly, the term is used loosely to refer to the combined action of sunlight and air, which cause oxidation and hydrolysis. Often photodegradation is intentionally avoided, since it destroys paintings and other artifacts. It is, however, partly responsible for remineralization of biomass and is used intentionally in some disinfection technologies. Photodegradation does not apply to how materials may be aged or degraded via infrared light or heat, but

Chemical reaction with peroxides catalysed by Fe(III/II)

economic sector

water chemistry parameter influencing dissolved oxygen concentration

chemical reaction in which water is broken down into oxygen and hydrogen

synchrotron radiation-based spectroscopy

chemical database

soil -exchange of gases between plant roots and the atmosphere

class of chemical compounds

type of soil formed by sedimentation in estuaries

chemical treatment procedures

Euxinia or euxinic conditions occur when water is both anoxic and sulfidic. This means that there is no oxygen (O2) and a raised level of free hydrogen sulfide (H2S). Euxinic bodies of water are frequently strongly stratified; have an oxic, highly productive, thin surface layer; and have anoxic, sulfidic bottom water. The word "euxinia" is derived from the Greek name for the Black Sea (Εὔξεινος Πόντος (Euxeinos Pontos)) which translates to "hospitable sea". Euxinic deep water is a key component of the Canfield ocean, a model of oceans during part of the Proterozoic eon (a part specifically kno

group of halogenated organic substances that are able to adsorb onto activated carbon

a process of rapidly measuring actively growing microorganisms through detection of adenosine triphosphate, or ATP

qualitative signifier of chemical purity level

Bioconversion, also known as biotransformation, is the conversion of organic materials, such as plant or animal waste, into usable products or energy sources by biological processes or agents, such as certain microorganisms. One example is the industrial production of cortisone, which one step is the bioconversion of progesterone to 11-alpha-Hydroxyprogesterone by Rhizopus nigricans. Another example is the bioconversion of glycerol to 1,3-propanediol, which is part of scientific research for many decades.

peer-reviewed scientific journal

scientific journal

peer-reviewed scientific journal

process of estimating or measuring the magnitude, frequency and duration of exposure to a potentially harmful agent

Vampirovibrionophyceae is a class of non-photosynthetic cyanobacteria.

international nonprofit organization

Type of mathematical model