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Chennai: With the hot bitumen mix plants that are used in laying roads coming under the focus of the Tamilnadu Pollution Control Board (TNPCB) for causing pollution, experts from the highways and environment sector welcome the move: they claim it will drastically change the way roads are laid.

TNPCB will be conducting an aerial survey this month and eventually complete the framing of guidelines governing these units based on an order from National Green Tribunal’s (NGT’s) Southern Bench here.

The bench was hearing an application which sought to seal seven hot mix plants near Sriperumbudur. They were closed down by the board for violating norms but continued to operate clandestinely at night.

Environmentalist Nithyanandam Jayaraman says, “Anything that is done for saving the environment is a good sign. Though I have little knowledge about the hot bitumen mix plants, any machinery or plant that uses fossil fuel definitely causes pollution. I am hearing for the first time that the bitumen plants have come under the purview of the pollution control agency of the State. The outcome of the survey will be an eye-opener for everyone, but the government departments, like highways and local bodies must follow the directive.”

Bitumen is best suited for road building in terms of cost of production, and it takes very less time for the workers to build a path with bitumen than any other form of road as it dries quickly. Since bitumen is a recyclable material, it can be re-used by melting. Moreover, whenever a pothole or crater appears on the road, it is very easy to repair.

The structure and thickness of the material makes it even easy to be re-layered over the old layer. They also provide better traction and skid resistance during commuting. But the small readymix hot plants used by the workers is a cause for concern. Many contractors use them at night for laying roads. Since the entire process involves heating bitumen, it causes air pollution. Despite this, for many years, bitumen plants never came under the purview of environmentalists or the pollution control agency.

Association of Tamilnadu Highway Engineers president and Highway Research Institute (Guindy) Deputy Director, A Venkatachalam, says, “This is first time I am hearing news about bitumen causing pollution. But I can say that bitumen plants work under the complete supervision of the authorities. Even the road contractors using such plants must fulfil criteria, and their quality is constantly checked. But I welcome the decision of the Tamilnadu Pollution Control Board for an aerial survey to study the pollution level and its plan to frame guidelines for hot bitumen mix plants. Because bitumen plants do cause pollution, anything that is done to safeguard nature must be welcomed.”

While bitumen plants have become a hot topic, road experts feel it is high time concrete was used as an effective replacement for bitumen as it doesn’t harm the eco-system. But some feel that concrete and bitumen have their disadvantages.

Listing out the points, Association of Tamilnadu Highway Engineers secretary R Deepak says, “While concrete is environment-friendly and long-lasting, it it has its limitations: constructing a concrete road is expensive, compared to bitumen. In case there are craters or cracks, the whole slab must be replaced or repaired. During rainy season, vehicles tend to slip or sometimes slide which might lead to accidents.”

WHAT IS IT?

Bitumen mix plant is a road construction equipment used for heating and mixing of aggregates, sand, gravel and stone dust. First the materials are heated at very high temperature of up to 1,000 degrees centigrade and then an appropriate proportion of bitumen is mixed in standard temperature and then it is transported to the work site for laying roads. There are two types of bitumen – one that occurs naturally and one that is derived by the distillation of petroleum.

http://newstodaynet.com/chennai/hot-mixing-plants-under-radar-pollution

Scientists may have significantly underestimated a dangerous source of pollution in the atmosphere, new research suggests.

A satellite study, published Monday in the journalNature Geoscience, has revealed nearly 40 previously unreported major sources of sulfur dioxide emissions – a pollutant that can cause multiple harmful health and environmental impacts and even exacerbate global warming.

Sulfur dioxide pollution can come from a variety of sources, both natural and industrial, including volcanoes, oil refineries and the burning of fossil fuels. Although it has a relatively short lifespan in the atmosphere – a few hours to a few days – its important for scientists to keep track of its presence to help inform air quality and climate models and create pollution-cutting policies.

Until now, scientists have mostly relied on emissions inventories drawing on national reports to identify the worlds sulfur dioxide sources and the amount of pollution theyre putting out. Satellite information has been able to help scientists further quantify sulfur dioxide emissions – but this method has mostly been useful when the scientists already know where the emissions are coming from. Thats because winds can help obscure sulfur dioxide hotspots, making it difficult to pick them out if their location isnt already known.

But in the new study, researchers from Canadas environment and climate change department and other institutions in the United States and Canada have described a new method that allows them to identify and map sulfur dioxide sources all over the world – including sources that may not have been previously identified or reported. And theyve found that anywhere from 7 to 14 million tonnes of sulfur dioxide may be missing from global inventories each year.

The new method combines satellite data with wind information to more accurately pinpoint pollution sources.

For each satellite measurement, we would know wind speed and direction and thus, using both pieces of information together, we can actually detect the location of where the sulfur dioxide is coming from, said Chris McLinden, a research scientist with Environment and Climate Change Canada and the new studys lead author. And so we were able to essentially do a global search for these sources.

The researchers then compared their results with three major global emissions inventories. Overall, they identified nearly 500 major sources of sulfur dioxide emissions, 75 of which were volcanic, and therefore natural, sources. Out of the remaining, human-caused sources, 39 could not be matched to any of the sources already identified in the inventories.

Of these 39 missing sources, there was a significant cluster in the Middle East. Fourteen were located there, and 12 of those corresponded with oil and gas operations, such as oil refineries. The rest of the missing locations were spread across the world, including Asia, Africa, Europe and the Americas, and corresponded largely with power plants.

Generally, these previously unreported sources tended to pop up in more developing types of nations where perhaps their legal requirements for reporting are not as rigorous as what we might be used to in the US and Canada, for example, McLinden said.

Altogether, emissions from these 39 missing sources came to about 7 million metric tonnes annually, or approximately 6 per cent of the total amount of sulfur dioxide produced by humans. However, the researchers noted that their method was only able to capture about half of the known anthropogenic sulfur dioxide sources in the world, owing to limitations in satellite technology – meaning that there may actually be twice as many missing sources out there as the method detected this time around.

[The satellites] have a relatively coarse spatial resolution – its not like these instruments that can picture the head of a dime from space, McLinden said. It measures maybe 10km at a time, 20km at a time. So you can imagine a very small source that doesnt emit that much sulfur dioxide would go unnoticed.

Extrapolating from the 50 per cent of known sources that the method was able to capture, then, the researchers suggested that there may be up to 14 million tonnes of missing sulfur dioxide emissions in the world.

Identifying these missing pollution sources – both sulfur dioxide and other types of emissions – is especially important for informing global air quality models, McLinden said, which can be used for everything from issuing health advisories to writing pollution and climate policies. The study, then, presents the alarming idea that the models to date have not been informed with the best and most accurate information – and highlights the need for better monitoring and reporting of pollution sources and the continued improvement of the kind of satellite technology that might aid in those endeavors.

When you have a large missing source somewhere, then youre not accounting for that pollution and youre providing a biased view of what the pollutions going to look like in the future, McLinden said.

http://www.scmp.com/news/world/article/1961420/scientists-discover-dozens-new-sources-dangerous-air-pollution-pumping

Divisional commissioner of Meerut Alok Sinha has asked the district administration to launch a crackdown on the use of pressure horns in heavy vehicle. The direction, which has been given to the district magistrate, has come almost five months after environment pollution control authority (EPCA) had asked the DM to impose a ban on the use of the pressure horns and submit an action-taken report on it.

However, no reply is filed by the administration on the issue so far.

On November 3, 2015, an NGO had approached the EPCA claiming that people residing in Meerut, Ghaziabad and Gautam Budh Nagar were facing the brunt of pressure horns used by heavy vehicles, especially the trucks.

 
Taking cognizance of the complaint, the EPCA had asked the DM to impose a ban on the horns and submit a status report.

 
“Loud and sharp noise of these horns not only make the elderly persons uncomfortable but the kids also start crying out of fear. Various organisations have raised the issue on several occasions. There is a complete ban on pressure horns in Delhi also. But in Meerut and nearby districts, nobody is paying heed to curb this menace,” NGO head Raman Tyagi had said in his complaint to EPCA.

 
Now, the divisional commissioner has expressed displeasure as a reply was not submitted to the EPCA so far. Additional district magistrate (ADM) Dinesh Chandra said that the RTO and other officials have been asked to give their reports in this regard and very soon they will be sending their reply to EPCA.

http://timesofindia.indiatimes.com/city/meerut/Crackdown-on-pressure-horns-in-the-offing-/articleshow/52542053.cms

Extreme weather conditions such as long spells of drought followed by heavy rains is leading to toxicity of food, a recent report released by the United Nations Environment Programme (UNEP ) said.

Major food crops such as maize, wheat, soyabeans are reacting to unusual weather patterns by retaining nitrates, which are toxic for both humans and animals, the report said, according to theReuters.

During the normal process, plants absorb the nitrates and convert them into amino acids and proteins. However, under drought-like conditions, this process slows down leading to accumulation of nitrates in plants.

Nitrates have a detrimental effect on humans and can intervene with functioning of red blood cells that transport oxygen throughout the body.

“Crops are responding to drought conditions and increases in temperature just like humans do when faced with a stressful situation,” Jacqueline McGlade, chief scientist and director of the Division of Early Warning and Assessment at UNEP, was quoted by the Reuters as saying.

Plants have the ability to accumulate several other chemicals such as Prussic Acid, Aflatoxins in response to extreme weather conditions.

Prussic Acid or hydrogen cyanide poisoning cases in humans were reported in Kenya in 2013 and in Philippines in 2015.

The UNEP official told Reuters that nearly 4.5 billion people around the world are exposed to aflatoxins. These chemicals killed at least 100 people in Kenya in 2004 and 300 persons suffered aflatoxin poisoning.

“Toxic crops can lead to neurological diseases among humans but the greatest challenge is the incidence of cancer,” Alex Ezeh, executive director of the African Population Health and Research Center, was quoted by the Reuters as saying.

http://www.ibtimes.co.in/unusual-weather-leading-toxicity-food-un-report-680916