Jan 08, · Where does pollution come from? Surprisingly, most ocean pollution comes from the land. According to the National Oceanic and Atmospheric Administration, 80 percent of marine pollution originates on land, in the form of runoff as pollution is swept into oceans through rivers or rain. Septic tanks, automobiles, farms, and ranches account for the most marine pollution When differences of atmospheric lead density between big and small cities largely went away, so did the difference in murder rates. Indoor Air Pollution. Avocado Mattress. Latest Jun 01, · Please use one of the following formats to cite this article in your essay, paper or report: APA. Lea, Robert. (, June 01). The Development of an Environmental ‘Swiss Army Knife’ to Tackle Water Pollution
Air Pollution and Your Health
When Rudy Giuliani ran for mayor of New York City inhe campaigned on a platform of bringing down crime and making the city safe again. It was a comfortable position for a former federal prosecutor with a tough-guy image, but it was more than mere posturing.
Sincerape rates had nearly quadrupled, murder had quintupled, and robbery had grown fourteenfold. New Yorkers felt like they lived in a city under siege. Wilson and George L. Kelling in an influential article in The Atlantic. But if you cracked down on small crimes, bigger crimes would drop as well.
Bratton had made his reputation as head of the New York City Transit Police, where he aggressively applied broken-windows policing to turnstile jumpers and vagrants in subway stations. And more: He decentralized police operations and gave precinct commanders more control, keeping them atmospheric pollution essay with a pioneering system called CompStat that tracked crime hot spots in real time.
The results were dramatic. Inthe New York Times reported that crime had plunged for the third straight year, the sharpest drop since the end of Prohibition. Sincerape rates had dropped 17 percent, assault 27 percent, robbery 42 percent, and murder an astonishing 49 percent. It was a remarkable public policy victory. But even more remarkable is what happened next. But even though the demographic bulge came right on schedule, crime continued to drop.
And drop, atmospheric pollution essay. And yet, atmospheric pollution essay, doubts remained. For one thing, violent crime actually peaked in New York City infour years before the Giuliani-Bratton era. By the time they took office, it had already dropped 12 percent. Newark: 74 percent, atmospheric pollution essay.
Los Angeles: 78 percent. There are, it turns out, plenty of theories. When I started research for this story, atmospheric pollution essay, I worked my way through a pair of thick criminology tomes. As they did, crime rates in New York and other cities went down. Another chapter told a story of demographics: As the number of young men increases, so does crime. There were chapters in my tomes on the effect of prison expansion.
On guns and gun control. On family. On race. On parole and probation. On the raw number of police officers. It seemed as if everyone had a pet theory. Ineconomist Steven Levitt, later famous as the coauthor of Freakonomicsatmospheric pollution essay, teamed up with John Donohue to suggest that crime dropped because of Roe v. Wade ; legalized abortion, they argued, atmospheric pollution essay, led to fewer unwanted babies, which meant fewer maladjusted and violent young men two decades later.
Maybe the end of the crack epidemic contributed to a decline in inner-city crime, but then again, maybe it was really the effect of increased incarceration, more cops on the beat, broken-windows policing, and a rise in abortion rates 20 years earlier. After all, they all happened at the same time.
To address this problem, the field of econometrics gives researchers an enormous toolbox of sophisticated statistical techniques. But, notes statistician and conservative commentator Jim Manzi in his recent book Uncontrolledeconometrics consistently fails to explain most of the variation in crime rates. After reviewing known field tests, Manzi found that only 20 percent demonstrated positive results for specific crime-fighting strategies, and none of those positive results were replicated in follow-up studies.
More prisons might atmospheric pollution essay control crime, more cops might help, and better policing might help. But the evidence is thin for any of these as the main cause. What are we missing? Experts often suggest that crime resembles an epidemic.
But what kind? Karl Smith, a professor of public economics and government at the University of North Carolina-Chapel Hill, has a good rule of thumb for categorizing epidemics : If it spreads along lines of communication, he says, the cause is information.
Think Bieber Fever. If it travels along major transportation routes, the cause is microbial. Think influenza. If it spreads out like a fan, the cause is an insect. Think malaria. Atmospheric pollution essay molecule? That sounds crazy. What molecule could be responsible for a steep and sudden decline in violent crime? InRick Nevin was a consultant working for the US Department of Housing and Urban Development on the costs and benefits of removing lead paint from old houses.
This has been a topic of intense study because of the growing body of research linking lead exposure in small children with a whole raft of complications later in life, including lower IQ, hyperactivity, behavioral problems, atmospheric pollution essay, and learning disabilities.
But as Nevin was working on that assignment, his client suggested they might be missing something. A recent study had suggested a link between childhood lead exposure and juvenile delinquency later on.
Maybe reducing lead exposure had an effect on violent crime too? That tip took Nevin in a different direction. It was leaded gasoline. Then, as unleaded gasoline began to replace leaded gasoline, emissions plummeted. Intriguingly, violent crime rates followed the same upside-down U pattern.
The two curves looked eerily identical, but were offset by about 20 years. So Nevin dove in further, digging up detailed data on lead emissions and crime rates to see if the similarity of the curves was as good as it seemed. It turned out to be even better: In a paper PDF he concluded that if you add a lag atmospheric pollution essay of 23 years, lead emissions from automobiles explain 90 percent of the variation in violent crime in America.
And with that we have our molecule: tetraethyl lead, atmospheric pollution essay, the gasoline additive invented by General Motors in the s to prevent knocking and pinging in high-performance engines. It was an exciting conjecture, and it prompted an atmospheric pollution essay wave of…nothing, atmospheric pollution essay.
Lots of things follow a pattern like that. So no matter how good the fit, if you only have a single correlation it might just be a coincidence. You need to do something more to establish causality. As it turns out, however, a few hundred miles north someone was doing just that. Although the association seemed plausible, she wanted to find out whether increased lead exposure caused increases in crime. But how? In fact, use of leaded gasoline varied widely among states, and this gave Reyes the opening she needed.
Conversely, in states where it declined quickly, crime would decline quickly. Meanwhile, Nevin had kept busy as well, and in he published a new paper looking at crime trends around the world PDF, atmospheric pollution essay. Sure, maybe the real culprit in the United States was something else happening at the exact same time, but what are the odds of that same something happening at several different times in several different countries?
Nevin atmospheric pollution essay lead data atmospheric pollution essay crime data for Australia and found atmospheric pollution essay close match. Ditto for Canada. And Great Britain and Finland and France and Italy and New Zealand and West Germany. Every time, the two curves fit each other astonishingly well. Just this year, Tulane University researcher Howard Mielke published a paper with demographer Sammy Zahran on the correlation of lead and crime at the city level.
In fact, Mielke has even studied lead concentrations at the neighborhood level in New Orleans and shared his maps with the local police. Put all this together and you have an astonishing body of evidence.
We now have studies at the international level, the national level, the state level, the city level, and even the individual level. Groups of children have been followed from the womb to adulthood, and higher childhood blood lead levels are consistently associated with higher adult arrest rates for violent crimes.
All of these studies tell the same story: Gasoline lead is responsible for a good share of the atmospheric pollution essay and fall of violent crime over the past half century.
Like many good theories, the gasoline lead atmospheric pollution essay helps explain some things we might not have realized even needed explaining. For example, murder rates have always been higher in big cities than in towns and small cities.
But as lead levels in gasoline decreased, the differences between big and small cities largely went away. And guess what? The difference in murder rates went away too. Today, homicide rates are similar in cities of atmospheric pollution essay sizes. Only gasoline lead, with its dramatic rise and fall following World War II, can explain the equally dramatic rise and fall in violent crime.
For starters, it turns out that childhood lead exposure at nearly any level can seriously and permanently reduce IQ. An estimated 2. Not only does lead promote apoptosis, or cell death, in the brain, but the element is also chemically similar to calcium.
When it settles in cerebral tissue, it prevents calcium ions from doing their job, something that causes physical damage to the developing brain that persists into adulthood. Only in the last few years have we begun to understand exactly what effects this has.
Air pollution – a major global public health issue
, time: 7:455 Effective Methods to Control Air Pollution (explained with diagram)
Jun 01, · Please use one of the following formats to cite this article in your essay, paper or report: APA. Lea, Robert. (, June 01). The Development of an Environmental ‘Swiss Army Knife’ to Tackle Water Pollution Essay on Environmental Pollution: Factors and Measures Taken – Essay 6 ( Words) India is the second most populous country in the World and home to over trillion people. It is a land of gorgeous and spectacular landscapes, abundant natural resources, and Jan 08, · Where does pollution come from? Surprisingly, most ocean pollution comes from the land. According to the National Oceanic and Atmospheric Administration, 80 percent of marine pollution originates on land, in the form of runoff as pollution is swept into oceans through rivers or rain. Septic tanks, automobiles, farms, and ranches account for the most marine pollution
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