Cell Signalling Section

Assessment No. 067

COSHH Process Safety Assessment

Name of Process

Brief Description


Use of Enhanced Chemiluminescence (ECL) as a detection system for Western Blotting.

Locations used RKCSB:

335, 341

Hazards Involved

1 Lauryl Sulphate Sodium salt (Sodium Dodecyl Sulphate – SDS) Code Red

2 2-[N-Morpholino]ethane sulfonic acid Code Red

3 Methanol Code Red

4 Antibodies containing Sodium Azide Code Red

5 Hydrochloric acid Code Red

6 Enhanced Chemiluminescence (ECL). There is no specific information available and the product is not classified as dangerous.

Nature of Hazards

1 SDS:

a) Harmful by inhalation and if swallowed

b) May cause sensitisation by inhalation

c) Irritating to eyes, respiratory system and skin

d) Risk of serious damage to eyes

e) LD50 ORL-rat 1288mg/kg

f) R 20/21/22 – 36/37/38 S 16 – 26 – 36/37/39

2 2-[N-Morpholino]ethane sulfonic acid (MES): a) Irritating to eyes, skin and respiratory system b) May be harmful by inhalation, if absorbed through

3 Methanol: skin and if swallowed c) R 36/37/38 S 26 – 36

a) Toxic by ingestion

b) Damaging if splashed in eyes

c) May cause headache and nausea

d) Chronic effects - damages the central nervous system, particularly the optic nerve and internal organs

e) LD50 5628 mg/kg oral, rat

f) Exposure limits ,OES, mg/m3 260 (long term, 8hr TWA)

g) Flammable. Flash point 12


h) R 11 – 23/24/25 – 39/23/24/25 S 7 – 16 – 36/37 – 45

4 Antibodies containing Sodium Azide:

a) May react with lead and copper plumbing to form highly explosive metal azides

b) May be fatal if swallowed

c) Poison

d) May cause cardiac disturbances

e) May be harmful by inhalation, ingestion or skin adsorption

f) May cause skin and eye irritation

g) Evidence of mutagenic effects

h) LD50 27mg/kg oral, rat

i) OES 0.3mg/m


(long-term, 8 hour TWA)

j) R 28-32-50/53 S 28-45-60-61

In the quantities contained in the antibodies, provided the correct precautions are taken,

Sodium azide presents little risk to the operator.

5 Hydrochloric acid:

a) Danger of poison

b) Causes severe burns

c) May be fatal if swallowed or inhaled

d) Causes damage to respiratory system, eyes and skin

e) Exposure limits OES, 7 mg/m


(long-term, 8hr TWA)

f) LD50 IPR – mouse 40mg/m


g) LD50 oral - rabbit 900mg/m


h) R 34 – 37 S 26 – 45

Precautions Required

Solutions containing HCL and Methanol are prepared in the fume hood.

Once prepared the solutions can be used on the bench. Use eye protection.

SDS and MES are weighed out wearing gloves and eye protection.

Gloves are worn throughout the procedure.


Gauges on fume hoods are used as indicators of airflow.

Fume hoods are serviced once a year.

Spillage Handling and Emergency Procedures

Worse case spill of SDS would be 500g. If a spill of more than 10g occurs, evacuate the laboratory and allow any dust to settle before re-entering. Wearing a respirator, mop up using dampened tissues, place in a bag and send for autoclaving. For spills of less than 10g clear the immediate area of personnel. Wearing face mask, eye protection and gloves, mop up with dampened tissues. Place the tissues in a bag for autoclaving. In all cases wash the area thoroughly with water.

Maximum spill of MES would be 100g. All spills can be swept up and placed in an autoclave bag and sent for autoclaving.

Maximum spill of methanol would be 2.5L. This would be in the fume hood. If the spill is more than 50ml use an absorbent blanket from the hazardous spill kit. Place in a labelled bag and allow the solvent to evaporate under the fume hood. Send for autoclaving. Smaller spills can be mopped up with tissues, placed in a bag and sent for autoclaving.

Maximum spill of antibodies would be a few µls. Wipe up with tissues and send for autoclaving.

Worse case spillage of concentrated HCl would be 200ml contained within the fume hood. Use an absorbent mat from the hazardous spill response kit, wearing rubber marigold gloves. This is then sealed in a bag and sent for autoclaving. For smaller spills mop up with tissues, wearing marigold gloves and place in bag for autoclaving. Wash the area down thoroughly with water after clearing up the spill.

Disposal of Waste Materials

Waste solutions can be washed down the sink with copious amounts of water.

All tips, tubes, gloves, etc are placed in an autoclave bag.

Local Exhaust Ventilation Used

Fume hoods in room 335 and 341

Documentation Issued


Laboratory Safety book



In the opinion of the Assessor, taking into account the toxic nature of the substances and the way they are used and controlled does a risk to health occur?

If yes describe how, where and what improvements are required to minimise those hazards or to achieve satisfactory control,

Taking into account the hazards of the substances and the way they are used and controlled, a risk to health does not occur.




A Gillies Position



Section Safety Officer


Is the work likely to change significantly in the foreseeable future?

If yes, give date for reassessment