PAHs Polycyclic Aromatic Hydrocarbons Detection

What are polycyclic aromatic hydrocarbons (PAHs)

PAHS Polycyclic aromatic hydrocarbons refer to a class of organic compounds with two or more benzene. Polycyclic aromatic hydrocarbons are hydrocarbons containing more than two benzene rings in their molecules, including more than 150 compounds such as naphthalene, anthracene, phenanthrene, and pyrene . The full English name  is polycyclic aromatic hydrocarbon , or PAHS for short . Some PAHs polycyclic aromatic hydrocarbons also contain nitrogen, sulfur and cyclopentane. Common PAHS polycyclic aromatic hydrocarbons with carcinogenic effects are mostly four- to six-ring fused ring compounds. The International Center for Research on Cancer ( IARC) ( 1976 ) lists 94 compounds that are carcinogenic to experimental animals. 15 of them are polycyclic aromatic hydrocarbons. Since benzo [a] pyrene is the first environmental chemical carcinogen discovered and is highly carcinogenic, benzo (a) pyrene is often used as the representative of polycyclic aromatic hydrocarbons. Accounting for 1%-20% of all carcinogenic polycyclic aromatic hydrocarbons . PAHs The main components of polycyclic aromatic hydrocarbons (PAHs) are the main eighteen compounds: naphthalene, acenaphthylene, acenaphthylene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo(a ) anthracene, chrysene, benzene (b) fluoranthene, benzo ( k) fluoranthene, benzo (a) Pyrene, indeno (1,2,3-cd) pyrene, dibenzo (a,h) anthracene and benzo (g,h,i) perylene, 1- methylnaphthalene, 2- methylnaphthalene.

The currently identified 24 common similar substances of PAHS mainly include:

Main sources and exposure opportunities of polycyclic aromatic hydrocarbons (PAHS). There are two types of pollution sources of polycyclic aromatic hydrocarbons(PAHS):natural sources and anthropogenic sources. Natural sources are mainly pollution caused by natural factors such as volcanic eruptions, forest fires and biosynthesis. Anthropogenic sources include toxic pollutioncaused byincomplete combustion or pyrolysis of various fossil fuels (such as coal, oil, natural gas, etc.), wood, paper, and other hydrocarbons in a reducing state. In addition, food also contains a certain amount of polycyclic aromatic hydrocarbons. The main source is that during the processing of food, especially the grease produced during smoking, roasting or scorching, benzo(a)pyrene can alsobethermallypolymerized.[a]in baked goods. During the storage process, some food storage packaging materials will contain a certain amount of polycyclic aromatic hydrocarbons;food dried on asphalt roads will be contaminated by asphalt. Polycyclic aromatic hydrocarbons in the atmosphere, water and soil can contaminate food, fruits and vegetables. Polycyclic aromatic hydrocarbons(PAHS)often exist in crude oil, creosote, tar, dyes, plastics, rubber, lubricants, anti-rust oils, release agents, gasoline retarder, capacitor electrolyte, mineral oil,asphalt and other petrochemical products , and also found in daily chemical products such as pesticides, charcoal, fungicides, mosquito coils, etc. In the electronic and electrical manufacturing industry,PAHSis usually used as a plastic additive in the production process. For example, when plastic particles are extruded and there is adhesion between the mold and the mold, a release agent must beadded, and the release agent may containPAHS.

Therefore, the current detection range of polycyclic aromatic hydrocarbons PAHS is:

● Consumer products such as electronics and motors ● Rubber products, plastic products, automotive plastics, rubber parts ● Food packaging materials, toys, container materials, etc. ● Other materials etc. Polycyclic aromatic hydrocarbons (PAHS) harm to humans, animals and plants Polycyclic aromatic hydrocarbons The main harmful parts of PAHS to the human body are the respiratory tract and skin. People who have been exposed to PAH-contaminated environments for a long time can cause acute or chronic injuries. Common symptoms include solar dermatitis, acne dermatitis, folliculitis and verrucous organisms. PAHs land on plant leaves. It will block the breathing holes of leaves, causing them to change color, shrink, curl, and fall off, affecting the normal growth and fruiting of plants. For example: soybean leaves contaminated by polycyclic aromatic hydrocarbons will turn red and fall off the plant, causing the fruit pods to be very small or not to set seeds. The carcinogenic effects of polycyclic aromatic hydrocarbons on animals have long been confirmed by experiments. Animal experiments have shown that polycyclic aromatic hydrocarbons have systemic effects on mice. If exposed to sunlight at the same time, the death of mice can be accelerated. When the mass concentration of polycyclic aromatic hydrocarbons was 0.01mg/L , the conditioned reflex activity of mice changed significantly. The regulatory requirements for polycyclic aromatic hydrocarbons (PAHS) in various countries so far have been determined through written laws or decrees in various countries and regions: EU 76/769/EEC ; German : GS mark , LFGB ; United States : EPA  ; China: GB , GB/T , GHZ . After discussions between ALDI Süd  and ALDI Nord , Germany has initially set the limits for PAHs as follows: A : General consumer products exposed to more than 30 seconds (such as handles, steering wheels, etc.): Benzo (a) pyrene < 1mg/kg, the sum of 16 PAHs is <10mg/kg. Contact with plastics below 30S , parts with occasional sexual contact: benzo (a) pyrene <20mg/kg, the sum of 16 PAHs <200mg/kg. B : Food, food contact, products that may be put into the mouth, and children's products benzo (a) pyrene <0.1mg/kg, and the total of 16 PAHs <1mg/kg. C : Other products Benzo (a) pyrene <1mg/kg, the sum of 16 PAHs <10mg/kg. D : GS Mandatory Testing of PAHs-- Polycyclic Aromatic Path Standard Source Description: The German Safety Technology Center (ZLS) Central Experience Exchange Office (ZEK) AtAV Committee passed the resolution on November 20 , 2007 ( see ZLS official website Announcement No. ZEK  01-08 ) requires mandatory inclusion of PAHs testing in the GS mark . This regulation has come into effect on April 1 , 2008. Products that cannot pass the PAHs test from the effective date will not be available .GS mark and successfully entered Germany. According to the requirements of the new regulations, the limits of PAHS in consumer product materials must comply with the following table:

Category 1 :  Materials that come into contact with food or items and toys that children under three years of age may put in their mouths

BaP : Not detectable  * (<0.2 mg/kg) , Total of 16 PAHs : Not  detectable  * (<0.2 mg/kg)

Category 2: Plastics, parts that are frequently in contact with the skin, parts that will be in contact for more than 30 seconds, and toys that are not standardized in Category 1

BaP : 1 mg/kg  , total of 16 PAHs : 10 mg/kg

Category 3: Plastics, parts with occasional sexual contact, that is, parts that are in contact with the skin for less than 30 seconds, or parts that have no contact with the skin

BaP : 20mg/kg , total of 16 PAHs : 200 mg / kg

If the test result is greater than the limit of Class 1 but meets the limit of Class 2, it needs to be tested according to the migration test of DIN EN1186 and 64 LFBG80.30-1 to confirm the test results. In 2011 , the German Safety Technology Certification Center ( ZLS ) determined to modify the PAH requirements . , officially released document ZEK 01.4-08 , expanding the number of PAH  items required for GS certification testing from 16 to 18 types. The two newly added PAHs  are: Benzo(j)fluoranthene and Benzo(e)pyrene , both of which are carcinogens. PAH limits in products : 

 The US Environmental Protection Agency has restrictions on PAHs. Click the link to view prevention and control measures . Measures to preventPAHS:Fuel must be burned fully to reduce the generation of polycyclic aromatic hydrocarbons. Strengthen indoor ventilation and reduce the indoor polycyclic aromatic hydrocarbon content. The productive inorganic powder method mainly causes systemic diseases such as pulmonary fibrosis, pneumoconiosis and dustosis. Organic dust can cause bronchial asthma,byssinosis,occupational hypersensitivity pneumonitis, non-specific chronic obstructive pulmonary disease, etc. Some dusts such as metal dust (nickel, chromium, arsenic, etc.) and asbestos can cause lung tumors. Dust acts on the respiratory mucosa, which initially manifests as hyperfunction such as capillary dilation and excessive secretion of mucus. This is a protective reaction, followed by hypertrophic changes and eventually atrophic changes due to nutritional deficiencies. Frequent exposure to dust can also cause diseases of the skin, ears, eyes and other organs. Toxic dust from lead, arsenic, and manganese canbe absorbed through the bronchus and alveolar walls, causing poisoning. Measures to prevent and controlPAHS:(1) Organizational measuresto ensure regular dust prevention work for production dust; adopt technological innovation measures for cleaner production;strengthen personal protection, conduct pre-employment physical examinations and regular physical examinations; formulate hygiene standards for dust . (2) Develop hydroelectric power generation to replace thermal power generationandresearch new energy sources;adopt and develop smoke and dust removal technology; Use regional collective heating measures to reduce particulate matter pollution in the air.