Routine for handling liquid chemical residues and aqueous solutions

Purpose

KTH and SU’s official policy is that hazardous substances must not be poured out in sinks, and that chemical waste must be disposed of as hazardous waste. This procedure describes which liquid chemical residues and aqueous solutions can be exempted from this rule and are allowed to be poured into sinks connected to the municipal sewer system. Please note that Stockholm University and KTH do not have any extra treatment of wastewater before it flows into the municipal sewer network.

Scope

This routine includes laboratory research and teaching activities within Stockholm University/KTH’s premises that are connected to Stockholm Water’s wastewater treatment plant via the sewer network.

Responsibilities

Everyone who performs laboratory and teaching activities at Stockholm University/KTH must follow this routine. The head of department/equivalent is responsible for their organisation’s management of chemicals and emissions.

Implementation

Chemical waste

The official policy is that chemical waste MUST be collected in appropriate containers, properly labelled, and handed in as hazardous waste to the commissioned waste supplier. Small amounts of liquid chemical residues can be diluted in the drain IF they meet ALL 5 requirements listed below:

1. The pH value must be at least 5 and no more than 11.5. Highly acidic or alkaline solutions can damage the sewer pipes.

1. The chemical must not be classified as environmentally hazardous. It cannot be marked with:
   a) H400–H413 hazard statements
   b) ED/ENV (endocrine disrupting/endocrine disrupting properties, for the environment) or EUH430 or EUH431
   c) PBT (persistent, bioaccumulative or toxic) or EUH440
   d) vPvB (very persistent and very bioaccumulative) or EUH441
   e) PMT (persistent, mobile, and toxic) or EUH450
   f) vPvM (very persistent, very mobile) or EUH451
2. The chemical must not be carcinogenic, mutagenic, or toxic to reproduction. It must not be labelled with hazard statements H340, H341, H350, H351, H360 or H361.
3. The chemical must not be classified as hazardous to health. It must not be labelled with hazard statements H300, H301, H310, H311, H330, H331, H334, H370–H372, or EUH380.
4. The chemical must not be strong-smelling. Vapours can diffuse out through water traps downstream in the sewer line.

• Residues of acetone and ethanol used to dry washed glass equipment may be discharged into the drain in small quantities. Ensure good ventilation.
• Potential exemptions exist for diluted aqueous solutions of hazardous substances where collection is difficult to implement, or where the handling of the collected amounts of solution is deemed to constitute a greater environmental burden than the environmental benefit of disposal as hazardous waste. Contact the department's laboratory safety coordinator for advice.

Biological liquid waste handling

Microorganisms

• If genetically modified: Must be disposed of as hazardous waste unless inactivated/sterilised. Liquid residues that are inactivated can only be released into sinks if they do not contain other hazardous substances.
• Wild type: Handle in accordance with the risk assessment. Take into account the risk of spreading infections with regard to health and the environment.

Antibiotic-containing waste

1. Biodegradable antibiotics – must be inactivated with a proven effective method before being handled as chemical hazardous waste. The method must be documented in the risk assessment or in local routines. Examples: Ampicillin, Carbenicillin, Chloramphenicol, Erythromycin, Penicillin, Amphotericin (Fungizone), Geneticin (G418), Gentamycin, Neomycin, Puromycin, Streptomycin, Sulfadoxine and Tetracycline.
2. Antibiotics that must always be disposed of as hazardous waste – Blasticidin, Ciprofloxacin, Enrofloxacin, Kanamycin, Nalidixic acid, Vancomycin, Zeomycin and Zeozin.

Note: Plates are considered combustible waste, and aqueous solutions are handled based on other additives.

Radioactive solutions

Radioactive water solutions may only be poured into the drain in accordance with rules defined by the Swedish Radiation Safety Authority (SSMFS 2018:1, Chapter 5, §§7–8, and SSMFS 2018:3) and only after consultation with Stockholm University/KTH’s radiation safety function. Contact the radiation safety coordinator via radsafety@su.se for further information.

Document in pdf

Routine for handling liquid chemical residues and aqueous solutions pdf, 235.2 kB.