The pound or pound-mass is a unit of mass used in both the British imperial and United States customary systems of measurement. Various definitions have been used; the most common today is the international avoirdupois pound, which is legally defined as exactly 0.45359237 kilograms, and which is divided into 16 avoirdupois ounces. The international standard symbol for the avoirdupois pound is lb; an alternative symbol is lbm, #, and ℔ or ″̶.
A barber is a person whose occupation is mainly to cut, dress, groom, style and shave hair or beards. A barber's place of work is known as a barbershop or the barber's. Barbershops have been noted places of social interaction and public discourse since at least classical antiquity. In some instances, barbershops were also public forums. They were the locations of open debates, voicing public concerns, and engaging citizens in discussions about contemporary issues.
A biocide is defined in the European legislation as a chemical substance or microorganism intended to destroy, deter, render harmless, or exert a controlling effect on any harmful organism. The US Environmental Protection Agency (EPA) uses a slightly different definition for biocides as "a diverse group of poisonous substances including preservatives, insecticides, disinfectants, and pesticides used for the control of organisms that are harmful to human or animal health or that cause damage to natural or manufactured products". When compared, the two definitions roughly imply the same, although the US EPA definition includes plant protection products and some veterinary medicines.
Chlorine dioxide is a chemical compound with the formula ClO2 that exists as yellowish-green gas above 11 °C, a reddish-brown liquid between 11 °C and −59 °C, and as bright orange crystals below −59 °C. It is usually handled as an aqueous solution. It is commonly used as a bleach. More recent developments have extended its applications in food processing and as a disinfectant.
A disinfectant is a chemical substance or compound used to inactivate or destroy microorganisms on inert surfaces. Disinfection does not necessarily kill all microorganisms, especially resistant bacterial spores; it is less effective than sterilization, which is an extreme physical or chemical process that kills all types of life. Disinfectants are generally distinguished from other antimicrobial agents such as antibiotics, which destroy microorganisms within the body, and antiseptics, which destroy microorganisms on living tissue. Disinfectants are also different from biocides—the latter are intended to destroy all forms of life, not just microorganisms. Disinfectants work by destroying the cell wall of microbes or interfering with their metabolism. It is also a form of decontamination, and can be defined as the process whereby physical or chemical methods are used to reduce the amount of pathogenic microorganisms on a surface.
An antimicrobial is an agent that kills microorganisms (microbicide) or stops their growth. Antimicrobial medicines can be grouped according to the microorganisms they act primarily against. For example, antibiotics are used against bacteria, and antifungals are used against fungi. They can also be classified according to their function. The use of antimicrobial medicines to treat infection is known as antimicrobial chemotherapy, while the use of antimicrobial medicines to prevent infection is known as antimicrobial prophylaxis.
Alachlor is an herbicide from the chloroacetanilide family. It is an odorless, white solid. The greatest use of alachlor is for control of annual grasses and broadleaf weeds in crops. Use of alachlor is illegal in the European Union and no products containing alachlor are currently registered in the United States.
The Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) is a United States federal law that set up the basic U.S. system of pesticide regulation to protect applicators, consumers, and the environment. It is administered and regulated by the United States Environmental Protection Agency (EPA) and the appropriate environmental agencies of the respective states. FIFRA has undergone several important amendments since its inception. A significant revision in 1972 by the Federal Environmental Pesticide Control Act (FEPCA) and several others have expanded EPA's present authority to oversee the sales and use of pesticides with emphasis on the preservation of human health and protection of the environment by "(1) strengthening the registration process by shifting the burden of proof to the chemical manufacturer, (2) enforcing compliance against banned and unregistered products, and (3) promulgating the regulatory framework missing from the original law".
Entecavir (ETV), sold under the brand name Baraclude, is an antiviral medication used in the treatment of hepatitis B virus (HBV) infection. In those with both HIV/AIDS and HBV antiretroviral medication should also be used. Entecavir is taken by mouth as a tablet or solution.
Sodium chlorite (NaClO2) is a chemical compound used in the manufacturing of paper and as a disinfectant.
Monochloramine, often called chloramine, is the chemical compound with the formula NH2Cl. Together with dichloramine (NHCl2) and nitrogen trichloride (NCl3), it is one of the three chloramines of ammonia. It is a colorless liquid at its melting point of −66 °C (−87 °F), but it is usually handled as a dilute aqueous solution, in which form it is sometimes used as a disinfectant. Chloramine is too unstable to have its boiling point measured.
Contaminated hemophilia blood products were a serious public health problem in the late 1970s up to 1985.
Lysol is a brand of American cleaning and disinfecting products distributed by Reckitt, which markets the similar Dettol or Sagrotan in other markets. The line includes liquid solutions for hard and soft surfaces, air treatment, and hand washing. The active ingredient in many Lysol products is benzalkonium chloride, but the active ingredient in the Lysol "Power and Free" line is hydrogen peroxide. Lysol has been used since its invention in the late 19th century as a household and industrial cleaning agent, and previously as a medical disinfectant.
Didecyldimethylammonium chloride (DDAC) is a quaternary ammonium compound used as antiseptic/disinfectant. It causes the disruption of intermolecular interactions and the dissociation of lipid bilayers. The bacteriostatic or bactericide activity of DDAC depends on its concentration and the growth phase of the microbial population. It is a broad spectrum biocidal against bacteria and fungi and can be used as disinfectant cleaner for linen, recommended for use in hospitals, hotels and industries. It is also used in gynaecology, surgery, ophthalmology, pediatrics, OT, and for the sterilization of surgical instruments, endoscopes and surface disinfection.
Disinfection by-products (DBPs) are organic and inorganic compounds resulting from chemical reactions between organic and inorganic substances such as contaminates and chemical treatment disinfection agents, respectively, in water during water disinfection processes.
A virucide is any physical or chemical agent that deactivates or destroys viruses. The substances are not only virucidal but can be also bactericidal, fungicidal, sporicidal or tuberculocidal.
Drinking water quality in the United States is generally safe. In 2016, over 90 percent of the nation's community water systems were in compliance with all published U.S. Environmental Protection Agency standards. Over 286 million Americans get their tap water from a community water system. Eight percent of the community water systems—large municipal water systems—provide water to 82 percent of the US population. The Safe Drinking Water Act requires the US EPA to set standards for drinking water quality in public water systems. Enforcement of the standards is mostly carried out by state health agencies. States may set standards that are more stringent than the federal standards.
The presence of mercury in fish is a health concern for people who eat them, especially for women who are or may become pregnant, nursing mothers, and young children. Fish and shellfish concentrate mercury in their bodies, often in the form of methylmercury, a highly toxic organomercury compound. This element is known to bioaccumulate in humans, so bioaccumulation in seafood carries over into human populations, where it can result in mercury poisoning. Mercury is dangerous to both natural ecosystems and humans because it is a metal known to be highly toxic, especially due to its neurotoxic ability to damage the central nervous system.
2,4-Dichlorophenoxyacetic acid is an organic compound with the chemical formula Cl2C6H3OCH2CO2H. It is usually referred to by its ISO common name 2,4-D. It is a systemic herbicide that kills most broadleaf weeds by causing uncontrolled growth, but most grasses such as cereals, lawn turf, and grassland are relatively unaffected.
Kimberly A. Prather is an American atmospheric chemist. She is a distinguished chair in atmospheric chemistry and a distinguished professor at the Scripps Institution of Oceanography and department of chemistry and biochemistry at UC San Diego. Her work focuses on how humans are influencing the atmosphere and climate. In 2019, she was elected a member of the National Academy of Engineering for technologies that transformed understanding of aerosols and their impacts on air quality, climate, and human health. In 2020, she was elected as a member of the National Academy of Sciences. She is also an elected Fellow of the American Philosophical Society, American Geophysical Union, the American Association for the Advancement of Science, American Philosophical Society, and the American Academy of Arts and Sciences.
