Air pollution is the result of the discharge into the atmosphere of foreign gases, vapours, droplets and particles, or of excessive amounts of normal constituents, such as the carbon dioxide and suspended particulate matter produced by the burning of fossil fuels. A growing body of evidence seems to show a consistent association between air pollution and health impairment of varying degrees. Such associations are found between acute pollution exposure and morbidity and mortality; chronic lower-level exposure and morbidity and mortality; exposure and impairment of function and performance; exposure and symptoms of sensory irritation; and exposure and other effects on well-being.

A relatively new feature of the effects of air pollutants is the association with long term global problems. Considerable uncertainty surrounds scenarios relating to the effect of increased levels of carbon dioxide, but some predictions are of major impact on climate. The most significant polluting substances are sulphur dioxide and the oxides of nitrogen produced by power stations burning coal or oil and motor cars. The phenomenon of acid deposition is widespread throughout northern temperate regions, and researchers have associated 'acid rain' with damage to wildlife and wildlife habitats, including freshwaters and forests. Both wet and dry acid deposition is associated with damage to artefacts and materials. More locally, environmental contamination has resulted from long-term use of materials such as asbestos and lead, whose full impact as air pollutants has emerged only recently.

Airborne toxic agents, including micro-organisms and other harmful agents such as respirable dust, may have long-term effects such as genetic damage, carcinogenesis, and shortened life expectancy. The effect on an individual of foreign substances in the ambient environment depends on his health and on the degree and duration of exposure. Symptoms may not be readily distinguishable and their medical assessment is not always easy. Practical difficulties also arise from the inadequacy of long-term sampling procedures and analytical techniques.

The recommendation of maximum permissible limits for international adoption is a complicated procedure. Countries vary greatly in the amount of airborne known toxic and harmful agents workers may be exposed to so that one country may allow exposure to a toxic agent to be up to 90 times greater than the exposure permitted in another country. Permissible limits are normally based on an exposure of eight hours a day for five days a week. Different considerations must apply when people are exposed briefly to high concentrations, when working periods are longer than normal, or when workers are subjected to additional stresses such as high temperatures or poor nutrition.

The variety of natural life forms, whether eco-regions, habitats, species or gene pools, is being endangered by human activity. This biodiversity ensures the regeneration of harvested resources and the maintenance of ecological processes, whether as a vital part of world heritage or for its own sake. It also provides resources for the development and improvement of domesticated crops and livestock, for recreation and tourism, and for research and education.

At the broadest level, biodiversity loss is driven by economic systems and policies that fail to value properly the environment and its resources, legal and institutional systems that promote unsustainable exploitation, and inequity in ownership and access to natural resources, including the benefits from their use. While some species are under direct threat, for example from hunting, poaching and illegal trade, the major threats come from changes in land use leading to the destruction, alteration or fragmentation of habitats.

Malaria is a parasite of red blood cells and the world's number one infectious disease. It is caused by infection of the liver with parasites of the genus Plasmodium, transmitted by the bite of infected anopheline mosquitoes Anopheles bifurcatus. The parasites cause the rupture of red blood cells and, in its worse cases, life-threatening anaemia, coma or death. The disease is characterized clinically by recurrent paroxysms of chills, high fever, seizures, sweating and prostration. It can lead to anaemia, kidney failure or rupture of the spleen. In man, malaria is produced by four specific parasites: Plasmodium vivax, P. malariae, P. ovale and P. falciparum. Falciparum malaria is the most life-threatening and has a fatality rate in untreated cases of 25%; it is transmitted by its African mosquito vector Anopheles gambiae.

Malaria is worsening in many parts of the world. It is a major threat to health and development, is primarily an environmental and socio-economic problem. Past reliance on narrow strategies is increasingly seen as the reason for the resurgence of this debilitating disease. The P. falciparum] parasite has continued to evolve resistance to almost all drugs in use (chloroquine, sulfadoxine/pyramethamine, and mefloquine). In areas of mosquito control, research with bed nets impregnated with pyrethroid insecticide offers hope of at least partial control of transmission of the disease in certain epidemiological situations. However, many people cannot afford the mosquito nets, which cost $5-10. Patients can usually be saved if they receive prompt medical treatment, but many of them cannot afford doctor's fees or the cost of travel, in total often less than $20.

Sin is a religious issue defined in different ways among different traditions. Within the Christian traditions sin is any word or deed or thought against the eternal law. In addition it includes violations of God's will that do not count as moral offences, i.e. idolatry. It is indifference or opposition to the will of God, the refusal of faith and love. It is an explicit or implicit claim to live independently of God, to put something else, be it the world or self, in His place. Paul Tillich states that sin, as opposed to sins, is the all prevailing problem of one's life. It is a state of existence before it is an act. It is simultaneously willed and fated separation from self, others and the Ground of Being.

Bacteriological or biological agents of warfare are living organisms (or infective material derived from them) which are intended to cause disease or death in animals, plants, or man, and which depend for their effects on their ability to multiply in the person, animal or plant attacked. Various living organisms (for example, rickettsiae, viruses and fungi), as well as bacteria, can be used as weapons. The use of epidemic warfare on a strategic scale is liable to lead to the infection of a very high proportion of the population attacked, and even if the attacking country were protected (by immunization) from some specific strain, changes to more virulent forms might overwhelm the level of immunity. The chief types of bacterial and viral agents developed or considered have included: anthrax (bacterial), which can cause death in 24 hours if lungs are attacked; brucellosis or undulant fever (bacterial), which is fatal in 5% of untreated cases; tick-borne encephalomyelitis and mosquito-borne equine encephalitis (viral), which have no effective treatment, can be fatal and can cripple the nervous systems of survivors; bubonic and pneumonic plagues (bacterial); psittacosis (viral) which can be fatal in up to 40% of cases; Rocky Mountain spotted fever (rickettsial) which can kill in 3 days; tularaemia (bacterial), for which the untreated rate of fatality is 5-8%; typhoid and cholera (bacterial) which is extremely contagious; Q-fever (rickettsial); and chikungunya and dengue fevers (viral). Smallpox is one of the deadliest epidemic viruses known, but has been exterminated in the wild; the only stocks are in high-security research establishments in the USA and Russia.