Research On The Status, Problems And Countermeasures Of Lead In Paints In China

Lead is a toxic heavy metal,which is widely used and has caused some environmental pollution and public health problems all over the world.Lead paint has become one of the main lead pollution sources in children's lead exposure.In recent years,the international community has advocated to take global action to formulate relevant laws and regulations to reduce or eliminate the risk of lead exposure caused by such paint.According to statistics,in 2016,the total output of coatings in China was eighteen million nine hundred and ninety-nine thousand and eight hundred tons,of which the output of exterior and interior coatings of buildings was about 5.77 million tons,accounting for 30.4 tons of the total coating amount,and the output of coatings for building steel structures was about 480,000 tons.Our country has formulated the coating product standard for the different use coating,among them,the interior decoration material interior wall coating,The limit value of lead content of indoor decoration materials waterborne wood coatings and consumer products in contact with human body is 90 ppm(soluble lead paint,exterior wall coating for building,anticorrosive coating for building steel structure,lead content limit value is 1000 ppm(total lead content).Therefore,by identifying the sources and main uses of leaded coatings,the research object of this paper is to study the interior and exterior coatings of buildings with the largest amount of lead used in our country and the coatings of building steel structures with large amount of leaded raw materials.The present situation of production and application of two kinds of coatings is investigated,the control policy of coating products in our country is analyzed,the lead content of exterior and interior coatings of buildings is tested,and the feasibility of lead-free transformation of architectural steel structure coatings is analyzed.The proposal of revising the standard lead content of paint is put forward.The total lead of 84 paint samples purchased from the market was tested and analyzed by means of experimental examination for the exterior and interior coatings of buildings.The experimental results were all undetected.The main reason for this result is that the waterborne technology of building interior and exterior coatings is becoming more and more advanced,coupled with the strict control of Chinese standards,which makes the market more environmentally friendly.However,from the perspective of the research results,In view of this,there is a certain difference between the limit value of lead in the standard of interior and exterior wall coatings of market buildings and that of our country.This study suggests that the relevant departments should revise the soluble lead content of 90 ppm to 90 ppm in the Internal Wall Coatings of Interior Decoration Materials and Interior Wall Coatings(GB18582-2008)and the limit of harmful substances in Building exterior Wall Coatings(GB24408-2009).The total lead content was revised to 90 ppm.In view of the construction steel structure coating,this study adopts the way of market research to collect the data of the main lead source of red Dan production enterprises,and from the existing alternative products,choose the more common calcium phosphite to replace red Dan.The feasibility of lead-free substitution is analyzed by using economic analysis method.The results show that lead-free substitution will cause an economic impact of about twenty-four million eighty-six thousand and six hundred yuan on the existing Hongdan production enterprises,but in view of the long-term benefits,Lead-free substitution will bring great environmental and social benefits,and the substitution of calcium phosphite for red Dan is more acceptable to the public at the price,so the substitution is feasible.