Using unleaded gasoline but the lead in the air increases!

Many Ho Chi Minh City residents, when going to the streets, must wear masks to limit breathing of harmful substances, especially emissions, dust and smoke . It is worrisome that some toxic substances in the air tend to increase.

Smoke car causes environmental pollution on Trans Asia road, Hoc Mon district, Ho Chi Minh City (Photo: TTD) Talking to PV, Mr. Nguyen Dinh Tuan, Head of the Ho Chi Minh City Environmental Protection Department, evaluated: When removing leaded gasoline from July 1, 2001, lead concentration in roadside air decreased significantly. But recently the concentration of lead in the air has shown a slight increase. 'We are closely monitoring this issue to find out why the concentration of lead in the air increases.

We also had a written request to the Department of Science and Technology of Ho Chi Minh City to determine whether the lead content in gasoline increased and exceeded the standard, but the agency answered that the lead content in gasoline is still within the limit. allowed " - Tuan said.

* How are substances very toxic to human health like benzene, toluene, xylene, sir?

According to the Ho Chi Minh City Environmental Protection Department, the noise measured in August 2006 at six monitoring stations with the highest noise level (max) did not meet the noise level, fluctuating in the range of 53.2. - 83.3dB (deciben), while the standard specifies a noise level not exceeding 75dB.The noise status exceeds the permissible standard.

- Volatile organic compounds are one of the most harmful air pollution compounds that are benzene, toluene, xylene. These volatile organic substances are derived from the combustion and evaporation of fuels, especially emissions from vehicles, including from domestic cooking . Until now our country has not yet Air quality environmental standards for these dangerous pollutants.

In 2005, the first year the Ho Chi Minh City Department of Environmental Protection piloted the above-mentioned pollutants at six air quality monitoring stations and took the standards of the US Environmental Protection Agency to attend. Examination of the problem of polluting these substances.

Measurement results in 2005 showed that the average annual benzene concentration at six monitoring stations ranged from 28.51 to 40.13 micrograms / m ³ .This number exceeds the US environmental protection agency's standards from 2.5 to 4.1 times.For toluene, xylene in the air meets US standards.In 2006, we continued to measure the above pollutants but had to wait until the end of the year to evaluate them because we needed measurements for all 12 months.

Technical staff of Ho Chi Minh City Environmental Protection Department measures indicators to assess air quality (Photo: CTV)

According to the results of air quality analysis in August 2006 (conducted by Ho Chi Minh City Department of Environmental Protection), the concentration of lead (Pb) was measured at six semi-automatic air quality monitoring stations. dynamic 0.2 - 2.17 micrograms / m ³ , still meeting air quality standards!But the concern is that if comparing this data with the monitoring results in July 2006, the lead concentration in some stations increased 1.4 - 2.2 times!

In comparison with the same period last year, the average monthly lead concentration monitoring results at most measuring stations increased by 1.1 to 1.6 times.

Reviewing all data on measuring lead levels in the first six months of 2006 and comparing with the first six months of 2005 showed that lead levels also increased by 1.2 to 2.3 times.

QUOC THANH made