Photographer: JC, Creative Commons
In this age of mass communication, it is no surprise that the media is an extremely influential and powerful force in today’s society. Research has shown that newspapers are the public’s primary source of information on topics pertaining to the environment.1
A 2001 study conducted on media coverage and public perception of beach closings in Southern California:
- Found that 74 percent of local residents obtained information on beach closings from the media.2
- The study concluded that the public’s perception of beach water quality is often in disagreement with the actual environmental conditions.
Typically, a person’s initial perception of water quality is based entirely on the aesthetic characteristics of the water and the surrounding environment. Aspects such as water color, clarity, odor, and the existence of waste material (litter and debris) influence a person’s opinion of water quality despite the fact that these aesthetic features often have little or no association with the actual physical, chemical, and biological quality of the aquatic system.3 Information in the media does little to enlighten the public about these and other misconceptions.
Unfortunately, the media’s portrayal of environmental issues is too often in reaction to disastrous events. As a result, the general public receives information of environmental threats after the fact, so that people are unable to play an influential and proactive role in the political process,4 particularly with problems relating to public health. Overall, people in the United States feel dissatisfied with water quality, though they rank social and economic concerns as more important. It is only when water quality issues become a health threat, such as when beaches are closed because of fecal pollution, that the public concern for water quality becomes a top priority.5 Therefore, it is vital that water resource management policies and practices be based on strong scientific information as opposed to the seemingly haphazard and sometimes contradictory information communicated to the general public through the mass media.
The majority of Americans depend on the media to help them comprehend the complexity of environmental issues.6 News media, such as newspapers, radio, television, and the Internet, have the ability to communicate information to vast and diverse audiences; therefore, these entities have both the opportunity to educate the public about water quality issues as well as the responsibility to use objective, accurate, and credible sources of information when conveying this information.
We have examined media coverage of a highly charged environmental issue: beach closings around Milwaukee, Wisconsin. This Great Lakes area has experienced numerous beach closings over the past several years, and the community is under intense public scrutiny for its periodic releases of partially and untreated sewage into Lake Michigan. We wanted to understand the “disconnect” between public perception and real health risks because it has both direct and indirect consequences on the resources in our communities. Public risk perception affects how people use water for both household and recreational purposes, which in turn influences how municipalities structure their water resource management policies.5
The BEACH Act
In response to growing public concern over the quality of coastal waters, the United States Congress passed the Beach Environmental Assessment and Coastal Health (BEACH) Act in 2000 to decrease or eliminate the health risk by reducing public exposure to recreational waters potentially contaminated with fecal pollution.
The BEACH Act mandates that levels of indicator bacteria, such as total coliforms, fecal coliforms, enterococci, or Escherichia coli (E. coli), be monitored in recreational water bodies.
Currently, the Environmental Protection Agency (EPA) recommends a water quality advisory when levels of the indicator bacteria exceed a certain level; for E. coli, which is the indicator often used in fresh water, the recommended limit is 235 colony forming units (CFU) in 100 milliliters of water.
These “indicator” bacteria are used to assess the potential public health risk because they are found in the gastrointestinal tracts of all warm-blooded animals. Their presence in surface waters is an indication of fecal pollution.7 Indicator bacteria do not necessarily pose a direct health risk to humans but do suggest the likely presence of harmful pathogens, such as Salmonella, Shigella, noraviruses, enteroviruses, Cryptosporidium, and Giardia, that are found in both human and non-human sources of fecal pollution and are considered health threats.8
Sources of bacterial pollution
Bacterial pollution in coastal waters is caused by a combination of point and nonpoint sources of pollution. Although point sources of bacterial contamination (e.g., industry, wastewater treatment facilities) are significant, nonpoint source pollution poses a much greater threat to the integrity of recreational water bodies because it comprises a diverse mixture of chemical and biological contaminants and is discharged from countless undefined sites within a given watershed. Pollutants accumulate in storm water as it is washed off impervious surfaces and discharged into local waterways. With increasing urbanization of the nation’s coastal areas, pollution of waterways by storm water is a growing concern. In a report to Congress, the EPA states that nonpoint sources of pollution are the greatest threat to the nation’s water quality.9 Examples of point and nonpoint sources of pollution include these:
- Sanitary sewage overflows (SSOs)
- Combined sewer overflows (CSOs)
- Septic systems
- Boating waste discharge
- Urban storm water runoff
- Agricultural runoff
- Waste from domestic pets and wildlife
Human health risk
Human fecal pollution is largely attributed to sewage overflows and constitutes the greatest public health threat because humans are reservoirs for human pathogens including bacteria, protozoa, and viruses.10 Animal fecal waste is also a serious health concern as it may contain pathogens such as Cryptosporidium, E. coli 0157:H7, or Salmonella and may enter recreational water bodies by means of contaminated runoff.11 Epidemiological data demonstrate that swimming in sewage-contaminated water is associated with gastroenteritis and inflammation of the eyes, ears, skin, nasal membranes, and upper respiratory tract. The likelihood of contracting these symptoms increases with the concentration of pollution and length of exposure to polluted water.12
Given the complexity of surface water systems and the potential health hazards associated with biological contaminants, better assessment tools are needed to evaluate regional water quality in the nearshore area of coastal waters.
Past studies have demonstrated that biological pollutants are difficult to track over long distances because of dilution and poor survivorship in large water bodies such as Lake Michigan.13
In these studies, it was shown that contamination at beach sites is most often associated with localized sources of pollution such as storm water runoff from outfalls located within the immediate vicinity of the beach, as opposed to regional contamination events such as sewage overflows which are more diffuse and accordingly impact a much larger portion of the nearshore region of Lake Michigan.
Studies conducted at beaches along Lake Michigan found that elevated E. coli levels frequently corresponded with rainfall and were attributed to the presence of large shore bird populations and runoff from storm water discharged from outfalls and impervious surfaces in the vicinity of swimming areas.13
As a result, localized contamination inputs can confound the detection of regional contamination events, making it difficult to assess the potential health risk. Simply testing for the indicator organism E. coli, which does not survive for extended periods of time in Lake Michigan, may not be sufficient. One study demonstrated a 90 percent reduction in fecal indicator bacteria within 6 to 8 hours of release into Lake Michigan.14 It is difficult to track the ultimate fate of sewage overflows and storm water as it is distributed in the nearshore region, and more advanced methods are needed for tracking major water pollution episodes in the Great Lakes.
Media coverage of environmental issues and public perception
It is extremely difficult for the average person to gauge the quality of water at a local beach site, so people turn to the media to obtain information about beach water conditions.1 However, environmental issues present a considerable challenge to reporters because they represent the clash between urban development and conservation interests and, as a result, are frequently met with political and economic resistance.15
A multitude of studies have been conducted throughout the country to investigate the reasons for beach closings. Beach closing investigations performed at urban beaches in Huntington Beach, California; Milwaukee, Wisconsin; and Chicago, Illinois have concluded that storm water runoff and resident waterfowl populations contribute significant loads of E. coli to beach areas and thus are the primary factors influencing beach water quality at these sites.13,17-19 Yet in most of these cases, the media blamed sewage overflows for the contamination.
Research suggests that media coverage of environmental issues is often a compromise between scientific evidence and economic interests.16 Given that U.S. newspapers rely heavily on the economic support of their advertisers, it is in their financial interest not to publish articles that conflict with the viewpoints of their primary financial contributors. For example, a recent study conducted on the media coverage of global warming determined that despite scientific evidence identifying global warming as a pressing environmental problem, the validity of this scientific theory continues to be discussed in the media, though rarely among scientists in the field.15 The authors of the study analyzed the content of 100 articles about the greenhouse effect and determined that the perspectives of big business, in this case the fossil fuel interests comprising the coal, oil, and automobile industries, were discussed at length in nearly all articles, while the scientific viewpoint generally reported to the public was that of the 1 percent of scientific experts who dispute the claim that global warming is real. Unfortunately, this phenomenon is not limited to global warming but is a common feature of the coverage controversial environmental issues get, especially those issues with economic implications.15
In addition, using mass media for environmental risk communication can be problematic because newspapers are not necessarily sources of balanced information. Because of time pressures, journalists work on the quick turnaround of stories and spend minimal time reviewing technical documents. Instead they rely on their key informants, which can potentially bias their interpretation of the scientific data.1
Even with the recent publicity and scientific evidence documenting the severe impacts of polluted storm water in coastal areas, people continue to perceive sewage overflows, major industries, and trash as the major sources of bacterial contamination in coastal systems.5 However, the evidence shows storm water is considered the largest threat to water quality in the United States.9 The urbanization of coastal areas has led to dramatic increases in storm water runoff and the subsequent degradation of water quality in coastal regions. Given the confusing and somewhat misleading information printed in the media regarding water pollution, it is not surprising that the public has a difficult time recognizing the leading sources of fecal pollution in surface waters.
Case study: Milwaukee, Wisconsin
The perception that human sewage pollution is the leading source of contamination at beaches is not limited to the popular press. In fact, a Natural Resources Defense Council (NRDC) report published in 2004 listed the percentage of posted water quality advisories for beaches in Milwaukee, Wisconsin, that were attributed to sewage contamination: 62 percent in 2000, 100 percent in 2001, and 90 percent in 2002.11 The NRDC’s report that 100 percent of the water quality advisories were caused from sewage pollution is questionable, based on the scientific studies conducted at one of the locations. South Shore Beach has had the highest number of water quality advisories of beaches in the area and was the subject of an intensive study of 40 surveys conducted from 2001 to 2003.13 This study demonstrated that South Shore Beach is impacted by local sources of pollution and rarely impacted by regional contamination events such as sewage overflows. Several points of evidence supported these conclusions:
Spatial water quality surveys that spanned the nearshore regions demonstrated that the high levels of E. coli were limited to the first 10 meters from the shoreline.
E. coli levels in offshore waters (50 to 150 meters) were below detectable limits.
Bacterial levels detected in storm water runoff collected directly from the parking lot was found to be between 9,000 and 100,000 E. coli per 100 milliliters.
The parking lot comprises almost two city blocks of impervious surfaces that drain into the beach area by way of a boat ramp.
Bacterial source tracking studies revealed that the elevated levels of E. coli from the swimming area were attributed to the large ring-billed gull and waterfowl populations and storm water runoff.
Out of 48 newspaper articles analyzed during this study, 40 percent concluded that sewage pollution was the primary source of bacterial contamination at beaches in southeastern Wisconsin, regardless of any scientific evidence to support these claims. Furthermore, 50 percent of the articles published cast doubt on the scientific premise that beach closings are caused by local sources of pollution, despite the scientific evidence of a direct correlation between large waterfowl populations and urban storm water runoff and the elevated bacteria levels in nearshore waters.
Public perception of water quality has direct implications on a person’s behavior and ultimately the integrity of the natural environment.2 Beach closings are complex environmental issues with both public health and economic consequences. Many coastal communities depend on income generated by tourism during the beach season, and consequently water quality advisories at local beaches can have potentially devastating impacts on the economy of a beach community. In addition, the public has become increasingly pessimistic about coastal water quality and beach health because of the rise in beach closures and water quality advisories nationwide. For that reason the public needs better information:
People must be given accurate and unbiased information concerning the primary threats impacting coastal water bodies so they can do their part to improve water quality conditions in these regions.
Scientists must reach out to educate journalists and the public to improve their understanding of environmental problems. By responding to media requests for information, participating in public forums, and utilizing websites to educate, scientists can help close the gap between scientific knowledge and public perception.
Through exposure to accurate information, personal experience, and persistence, people will become informed about the true threats to the environment and perhaps alter their daily activities accordingly.
© 2005, American Institute of Biological Sciences. Educators have permission to reprint articles for classroom use; other users, please contact email@example.com for reprint permission. See reprint policy.nhà cái tặng tiền cược miễn phí tháng