Clean Air Act

The air in modern homes and offices is pretty clean,but not as clean as it might be.Often it contains small amounts of volatile(挥发性的）,poisonous,organic compounds.Long-term    1     to these is a bad thing,so clearing them out of the air people breathe is widely accepted as     2    

Finding an effective way to do so has proved difficult.But Stuart Strand, Long Zhang and Ryan Routsong, of the University of Washington,in Seattle,think they have succeeded,As they report in Environmental Science and Technology, their method involves     3     a gene from a rabbit into a popular indoor plant nicknamed Devil's vine—a type of ivy hat is so called because it is    4     difficult to kill.

The idea of     5     plants to de- pollute   the atmosphere inside buildings has been around for decades-but has met with only qualified success. One experiment involving unmodified spider plants,for example,showed that they are indeed     6     of removing formaldhyde (甲醛) from the air.The     7     is that to make much of a difference in a space as large as a house would require turning most of the rooms into spider-plant forests.

Dr Strand, Dr Zhang and Mr Routsong thus sought something suitably transgenic ( 转 基 因 的),but that does not flower indoors. The plant they settled on was Devil's vine,     8     because of its toughness.With the help of a bacterium,they were able to ferry the rabbit version of the gene into the plant's chromosomes(染色 体),and thus to,engineer a type of Devil's vine able to produce an air-cleaning substance. To test the     9     of their idea, the researchers put their modified ivy to work inside greenhouses filled with air containing high levels of harmful substances.The plants performed well,reducing the harmful substances in air to     10    .

5 . You’ve heard that plastic is polluting the oceans — between 4.8 and 12.7 million tonnes enter ocean ecosystems every year. But does one plastic straw or cup really make a difference? Artist Benjamin Von Wong wants you to know that it does. He builds massive sculptures out of plastic garbage, forcing viewers to re-examine their relationship to single-use plastic products.

At the beginning of the year, the artist built a piece called “Strawpocalypse,” a pair of 10-foot-tall plastic waves, frozen mid-crash. Made of 168,000 plastic straws collected from several volunteer beach cleanups, the sculpture made its first appearance at the Estella Place shopping center in Ho Chi Minh City, Vietnam.

Just 9% of global plastic waste is recycled. Plastic straws are by no means the biggest source (来源) of plastic pollution, but they’ve recently come under fire because most people don’t need them to drink with and, because of their small size and weight, they cannot be recycled. Every straw that’s part of Von Wong’s artwork likely came from a drink that someone used for only a few minutes. Once the drink is gone, the straw will take centuries to disappear.

In a piece from 2018, Von Wong wanted to illustrate (说明) a specific statistic: Every 60 seconds, a truckload’s worth of plastic enters the ocean. For this work, titled “Truckload of Plastic,” Von Wong and a group of volunteers collected more than 10,000 pieces of plastic, which were then tied together to look like they’d been dumped (倾倒) from a truck all at once.

Von Wong hopes that his work will also help pressure big companies to reduce their plastic footprint.

6 . A great amount of dark, sticky tar(焦油)was reported along Israel's coast last week. An off-shore oil tanker is believed to have leaked out.

The floating oil can form tar balls as it is pushed by wind and waves on the ocean's surface. After a violent storm, the tar balls were seen ashore. Israel has about 190 kilometers beaches. The tar has already had a big effect on the local wildlife. Volunteers were working quickly to rescue sea birds, turtles and fish. Some animals were covered in oil or tar. Others had swallowed it. The body of a young whale was found washed up on shore. The whale appeared to have died after swallowing a black oily liquid.

The government has asked people to avoid going to the beach, since tar exposure can make people sick and do harm to the skin. A number of volunteers had to be taken to the hospital after breathing in the air polluted by chemicals from the tar.

Experts from Israel and countries in Europe are still trying to figure out exactly what happened. The leak is believed to have taken place about a week ago, when there were strong storms in the area. Israel believed that a ship leaked tens or even hundreds of tons of oil in the Mediterranean. Experts are working together to review satellite images of ships that passed through the area, and they have a list of about 10 ships that are the most likely ones to leak out.

The Israel Nature and Parks Authority warned that the “consequences will be seen for years to come”. Israeli environment minister Gila Gamliel said on Saturday that there is no more floating oil visible off Israel's coast, “which is a very animative condition”. However, the ministry warned that large waves are forecast this week. The waves could carry the sticky tar from beach to beach, which could make clean-up efforts more difficult.

7 . Farms are battlefields, forcing growers to fight against greedy pests and aggressive weeds in never- ending, costly campaigns that often involve chemical weapons. Those weapons also harm innocent bystanders such as bees and fish. Now, a study chart's impressive shifts in recent decades as U. S. farmers have changed their types of pesticides. Birds and mammals have been affected less, whereas pollinators are suffering. The toxic (有毒的) impact on land plants has also increased sharply, likely because farmers are using increasing kinds of chemicals to fight weeds that have become resistant to common herbicides( 除草剂).

As a research shows, in recent decades, the amount of pesticides used in the United States has gone down by about 40% . But active ingredients have become more powerful. For example, fast-acting pesticides are very toxic. Some require as lite as 6 grams per hectare, compared with several kilograms of the older pesticides. Ralf Schulz, an ecotoxicologist, wondered whether overall toxicity in the ecosystem had changed. A few studies had looked at certain compounds and organisms, but nothing had been done on a national scale.

Schulz and colleagues started with U. S. Geological Survey data on self- reported pesticide use by U. s. farmers from 1992 to 2016. They also gathered toxicity data from the U. S. Environmental Protection Agency on those same compounds-381 in all, The good news is that total toxicity decreased more than 95%, for birds and mammals from 1992 to 2016, largely because of the phaseout (逐步停止) of older pesticides. Toxicity for fish declined by less- about one-third.

Schulz hopes more researches will help policymakers and others think more about the complexity of pest and weed control, and wild species, in order to reduce unintentional harm. The rising toxicity in plants could lead to less diverse habitat and food resources that eventually spread to animal populations, potentially causing losses. “The patterns in the U. S. pesticide use and toxicity data should be a warning for the rest of the world, much of which seems to be leaning more heavily on pesticide use rather than ecological interactions for pest control,” Schulz said.

8 . In recent years, Ethiopia has become a regional leader in solid waste management. Last year, the country transformed the landfill (垃圾填埋场) in Addis Ababa into a new waste-to-energy plant, the first such project on the continent. The plant incinerates up to 1, 400 tonnes of waste every day, about 80 percent of the city's rubbish, supplying the capital with 25 percent of its household electricity needs.

However, despite these important steps, challenges remain in Ethiopia. Although the country has permitted the Basel, Stockholm and Rotterdam conventions, laws and policies for environmentally sound management of hazardous (有害的) wastes are still not effective in pre- venting littering waste illegally.

To help Ethiopia meet these challenges, the Chemicals and Waste Management Program is supporting the country with a three-year project to enhance its capacity for sound management of hazardous wastes.

In the initial stages, a project management unit will be formed, made up of many representatives from government departments and private organizations. This unit will be responsible for reviewing and assessing Ethiopia's current legal system, which, despite numerous advances in recent years, does not specifically target the recycling of hazardous waste. Once legal gaps are identified, the project will seek to update existing policies and strategies.

Many people in Ethiopia are not aware of the possible effect of environmental damage and the need to report such crimes to the police. To resolve this pressing issue, Ethiopia will be conducting a series of capacity-building activities, including creating awareness-raising programs, training trainers and providing equipment.

Ethiopia will also work to establish a national mechanism for chemicals and waste management by engaging government departments and civil society groups. Authorities will also make budgetary provisions (预算拨款) in national, regional and institutional planning to ensure funding for these activities is sustainable even after the project's completion.