The Roman deity, Mercury, was the god of trade, commerce, thievery, and messengers. His reputation as a cunning and swift messenger led to the modern adjective,mercurial, meaning labile, volatile, and erratic. Many contemporary scientists who study mercury would emphatically agree that its behavior in the environment and in the laboratory often seems erratic and mysterious. Indeed, it was only relatively recently that we became aware of the global nature of mercury contamination, partly because of the difficulty in detecting it at the extremely low concentrations that are typical in air and water. Thus, we encounter an apparent paradox fitting...

Mercury and cinnabar, the common ore of mercury, were known and used by ancient people in Africa, Asia, Central America, Europe, Mexico, and South America. Archaeologists have shown that cinnabar was mined and mercury was produced more than 8000 years ago in Turkey. Cinnabar was a multiuse pigment in many parts of the ancient world, and mercury was used for gilding or placer gold amalgamation. Mercury was the earliest known treatment for syphilis, and its use is described in the Canon of Medicine by the Persian physician Ibn Sina (Avicenna) in 1025 ce.

Even though cinnabar and mercury are found...

Mercury (Hg) exists in a large number of physical and chemical forms with a wide range of properties. Conversion between these different forms provides the basis for mercury’s complex distribution pattern in local and global cycles and for its biologic enrichment and effects. Since the 1960s, the growing awareness of environmental mercury pollution has stimulated the development of more accurate, precise and efficient methods of quantifying mercury and its compounds in a wide variety of matrices. During recent years new analytical techniques have become available that have contributed significantly to the understanding of mercury chemistry in natural systems. In particular,...

Mercury, with an average atomic weight of 200.59 ± 0.02, has seven stable isotopes and numerous radioactive isotopes. The representative abundance percentages (De Laeter et al., 2003) of the individual isotopes are ¹⁹⁶Hg (0.15 ± 0.01), ¹⁹⁸Hg (9.97 ± 0.20), ¹⁹⁹Hg (16.87 ± 0.22), ²⁰⁰Hg (23.10 ± 0.19), ²⁰¹Hg (13.18 ± 0.09), ²⁰²Hg (29.86 ± 0.26), and ²⁰⁴Hg (6.87 ± 0.15). The provided uncertainties are rather large, presumably caused either by measurement uncertainties or as a result of actual variations in natural isotope abundance. All radiogenic Hg isotopes, including ¹⁹⁶Hg (t_1/2= 64.14 hours) and ²⁰³Hg (t_1/2= 46.612 days)...

Mercury in the environment is of increasing concern globally because it can travel long distances through the atmosphere. For example, atmospheric transport and deposition of mercury from lower latitudes to the Arctic environment poses environmental and human health risks, despite few sources within the Arctic. On a more local scale, atmospheric chemical reactions and meteorologic processes can determine whether mercury deposits near sources or circulates globally. Understanding the chemistry and transport of atmospheric mercury is thus vitally important for managing mercury pollution.

There remain several critical uncertainties surrounding the behavior of mercury in the atmosphere. The global biogeochemical budget of...

Mercury (Hg), especially in its more toxic and bio-accumulative form as methylmercury (MeHg), is an important environmental health concern (Clarkson, 1994; Wolfe et al., 1998; Wiener et al., 2003; Pirrone and Mahaffey, 2005; Mergler et al., 2007). Therefore, in recent years there has been a global effort to limit its input to the atmosphere, especially from anthropogenic sources. Many regulations limiting Hg emissions from specific sources in developing countries, and elsewhere, are already in place, mandated, or likely to happen in the future (USEPA, 1997, 2008; UNEP, 2009). As these regulations are implemented, there is a crucial need to document...

Mercury (Hg) cycling in soils is critical to our understanding of Hg accumulation and loss in the environment. Soils have a large capacity to store Hg, and small changes in Hg dynamics can have large effects on ecosystem function and biologic exposure. In most watersheds, the terrestrial components receive and retain considerably more atmospheric Hg deposition than the associated freshwater bodies. This can be attributed to: (a) the typically larger areal extent of the watershed as compared with the water body, (b) the role of a vegetative canopy in expanding the effective surface area, and (c) soil’s high capacity to...

Long-range atmospheric transport of anthropogenic mercury (Hg) emissions has led to Hg deposition well in excess of natural levels throughout much of Europe, North America, and other areas (Iverfeldt, 1991; Mierle and Ingram, 1991; Fitzgerald et al., 1998; Slemr et al., 2003). This deposition has contributed to the accumulation of Hg in the aquatic food chain (Lindqvist et al., 1991; Kamman et al., 2005). It is now common for some species of fish to contain Hg near or above levels deemed harmful to human health, even in relatively remote areas such as boreal areas of Fenno-Scandia (Munthe et al., 2004)...

The transformations and fate of the global, regional, and local contaminant mercury (Hg) have been studied extensively in freshwater ecosystems for the past 15 years (Watras et al., 1998; Driscoll et al., 2007; Evers et al., 2007). Much is known about the processes involved in methylmercury (MeHg) production and flux and MeHg bio-accumulation and trophic transfer in lakes, ponds, and reservoirs. Moreover, studies conducted in a wide range of freshwater ecosystems have revealed specific suites of attributes that predispose certain systems to being hot spots of MeHg bio-accumulation. Evers et al. (2007) defines a biologic Hg hotspot as “a location...

The study of mercury in marine ecosystems is necessary to understand and minimize the chronic, sublethal toxicity due to exposure to organomercury in the marine environment and marine resources. The combination of the complex biogeochemical cycling of mercury with similarly complex marine ecologic processes make this study challenging, requiring a multitude of scientific approaches to answer specific questions about mercury in marine ecosystems. Some of these questions relate to fish consumption, with the most obvious being “Which fish are the healthiest to eat” and “Is there a limit to how much is healthy?” Other questions relate to the source of...

The toxic effects of mercury (Hg) in fish and wildlife have been extensively reviewed (e.g., Scheuhammer, 1987; Heinz, 1996; Thompson, 1996; Wiener and Spry, 1996; Wiener et al., 2003; Scheuhammer et al., 2007). However, some research on the subtle effects of methylmercury (MeHg) on brain chemistry, hormones, and reproductive success and the implications for population-level effects in certain at-risk species, such as the common loon (Gavia immer) have not been reviewed previously. A number of the newer studies demonstrate that current levels of environmental MeHg exposure are sufficient to cause significant biological impairment, both in individuals and in whole populations,...

Increasingly the public, governmental agencies, and public policy makers, as well as health professionals and ecologists, want to understand the risks that derive from mercury in the environment. The risks are to individuals of a species, including humans, and to populations, communities, and ecosystems. The risks can be sublethal as well as lethal, resulting in altered behavior, impaired reproductive success and/or lower survival, and eventually decreases in populations. Toxic effects can be at the biochemical, cellular, or organ level. High levels of methylmercury in individual organisms can lead both to detrimental effects on the individuals themselves, and also to other...

Historically, humans have suffered toxic effects of mercury as a result of purposeful as well as accidental exposures. Mercury has been used in medical remedies for centuries. Some scientists believe it was used during the Middle Ages to treat diseases that manifested with skin lesions, such as syphilis and leprosy (Goldwater, 1972; Rasmussen et al., 2008). Earlier medicinal uses have been documented in China, India, and the Middle East (Goldwater, 1972). Mercury is still used medicinally in some parts of the world (Liu et al., 2008; Saper et al., 2008).

The toxicity of mercury and mercury-containing remedies has also long...

In the 1950s, a mysterious epidemic hit the Japanese fishing village of Minamata. An unusual number of residents began to exhibit odd behaviors, such as slurring their speech, stumbling, or trembling uncontrollably. Hearing and vision impairments developed in some, and paralysis in others. The malady even affected newborn babies, some of whom were born with physical deformities, cerebral palsy, or mental retardation.

An investigation eventually linked the village’s strange outbreak of health problems to a pollutant in Minamata Bay: mercury. For years, a local chemical plant had discharged organic mercury into the bay’s waters, where the pollutant moved up the...

Environmental justice and sustainable development are two recent concepts that have provided exciting and normative framework for public debate and environmental planning in many countries. Although both concepts are difficult to define and lack precision as analytic policy tools, each paradigm has a potential to effect long-lasting changes on how we relate to and manage the environment (Agyeman, 2005). What makes the concepts unique is that both promote environmental equity using communitarian-approach to issues at the local, regional, and global scales.

As defined by Bullard (1994), environmental justice “embraces the principle that all people and communities are entitled to equal...

Persistent, bio-accumulative, and toxic (PBT) pollutants are of particular concern to environmental and public health policy makers because of their potential for adverse multi-generational effects that often range far beyond their site of initial release. PBTs, like mercury, which cause adverse neurodevelopmental effects, raise additional concerns because of their long-term individual and societal impacts as well as ethical considerations relating to the involuntary nature of the exposure. Personal and societal concerns about the well-being of children are also paramount. These attributes underpin the priority status that mercury pollution has been afforded by many states as well as their focus on...