Class 6.1 Toxic substances
Criteria
The heading of Class 6.1 covers substances of which it is known by experience or regarding which it is presumed from experiments on animals that in relatively small quantities they are able by a single action or by action of short duration to cause damage to human health, or death,by inhalation, by cutaneous absorption or by ingestion.
NOTE:Genetically modified microorganisms and organisms shall be assigned to this Class if they meet the conditions for this Class.
Substances of Class 6.1 are subdivided as follows:
T Toxic substances without subsidiary hazard:
T1Organic, liquid;
T2Organic, solid;
T3Organometallic substances;
T4Inorganic, liquid;
T5Inorganic, solid;
T6Liquid, used as pesticides;
T7Solid, used as pesticides;
T8Samples;
T9Other toxic substances;
T10Articles;
TFToxic substances, flammable:
TF1Liquid;
TF2Liquid, used as pesticides;
TF3Solid;
TSToxic substances, self-heating, solid;
TWToxic substances, which, in contact with water, emit flammable gases:
TW1Liquid;
TW2Solid;
TOToxic substances, oxidizing:
TO1Liquid;
TO2Solid;
TCToxic substances, corrosive:
TC1Organic, liquid;
TC2Organic, solid;
TC3Inorganic, liquid;
TC4Inorganic, solid;
TFCToxic substances, flammable, corrosive;
TFWToxic substances, flammable, which, in contact with water, emit flammable gases.
Definition
For the purposes of ADR:
LD50(median lethal dose) for acute oral toxicityis the statistically derived single dose of a substance that can be expected tocause death within 14 days in 50 per cent of young adult albino rats when administered by the oral route. The LD50value is expressed in terms of mass of test substance per mass of test animal (mg/kg);
LD50 for acute dermal toxicityis that dose of the substance which, administered by continuous contact for 24 hours with the bare skin of albino rabbits, is most likely to cause death within 14 days in one half of the animals tested. The number of animals tested shall be sufficient to give a statistically significant result and be in conformity with good pharmacological practice. The result is expressed in milligrams per kg body mass;
LC50 for acute toxicity on inhalationis that concentration of vapour, mist or dust which, administered by continuous inhalation to both male and female young adult albino rats for one hour, is most likely to cause death within 14 days in one half of the animals tested. Asolid substance shall be tested if at least10% (by mass) of its total mass is likely to be dust in a respirable range, e.g. the aerodynamic diameter of that particle-fraction is 10 μm or less. A liquid substance shall be tested if a mist is likely to be generated in a leakage of the transport containment. Both for solid and liquid substances more than90% (bymass) of a specimen prepared for inhalation toxicity shall be in the respirable range as defined above. The result is expressed in milligrams per litre of air for dusts and mists or in millilitres per cubic metre of air (parts per million) for vapours.
Classification and assignment of packing groups
Substances of Class 6.1 shall be classified in three packing groups according to the degree of danger they present for carriage, as follows
Packing group I: highly toxic substances
Packing group II: toxic substances
Packing group III: slightly toxic substances
Substances, mixtures, solutions and articles classified in Class 6.1 are listed in Table A of Chapter3.2. The assignment of substances, mixtures and solutions not mentioned by name in Table A of Chapter 3.2 to the relevant entry of sub-section 2.2.61.3 and to the relevant packing group in accordance with the provisions of Chapter2.1, shall be made according to the following criteria in 2.2.61.1.6 to 2.2.61.1.11.
To assess the degree of toxicity, account shall be taken of human experience of instances of accidental poisoning, as well as special properties possessed by any individual substances: liquid state, high volatility, any special likelihood of cutaneous absorption, and special biological effects.
In the absence of observations on humans, the degree of toxicity shall be assessed using the available data from animal experiments in accordance with the table below:
|
|
Packing group |
Oral toxicity LD50 (mg/kg) |
Dermal toxicity LD50 (mg/kg) |
Inhalation toxicity by dusts and mists LC50 (mg/l) |
|
Highly toxic |
I |
≤ 5 |
≤ 50 |
≤ 0,2 |
|
Toxic |
II |
> 5 ve ≤ 50 |
> 50 ve ≤ 200 |
> 0,2 ve ≤ 2 |
|
Slightly toxic |
III a |
> 50 ve ≤ 300 |
> 200 ve ≤ 1000 |
> 2 ve ≤ 4 |
a Tear gas substances shall be included in packing group II even if data concerning their toxicity correspond to packing group III criteria.
Where a substance exhibits different degrees of toxicity for two or more kinds of exposure, it shall be classified under the highest such degree of toxicity.
Substances meeting the criteria of Class 8 and with an inhalation toxicity of dusts and mists (LC50)leading topackinggroup I shall only be accepted for an allocationtoClass6.1 if the toxicity throughoral ingestion or dermal contact is at least in the range of packing groups I or II. Otherwisean assignment to Class8 shall be made if appropriate (see 2.2.8.1.4.5).
The criteria for inhalation toxicity of dusts and mists are based on LC50 data relating to 1-hour exposure, and where such information is available it shall be used. However, where only LC50 data relating to 4-hour exposure are available, such figures can be multiplied by four and the product substituted in the above criteria,i.e. LC50 value multiplied by four (4hour) is considered the equivalent of LC50 (1 hour).
Inhalation toxicity of vapours
Liquids giving off toxic vapours shall be classified into the following groups where "V" is the saturated vapour concentration (in ml/m3 of air) (volatility) at 20 °C and standard atmospheric pressure:
|
|
Packing group |
|
|
Highly toxic |
I |
Where V ≥ 10 LC50 and LC50 ≤ 1 000 ml/m3 |
|
Toxic |
II |
Where V ≥ LC50 and LC50 ≤ 3 000 ml/m3 and the criteria for packing group I are not met |
|
Slightly toxic |
IIIa |
Where V ≥ 1/5 LC50 and LC50 ≤ 5 000 ml/m3 and the criteria for packing groups I and II are not met |
a Tear gas substances shall be included in packing group II even if data concerning their toxicity correspond to packing group III criteria.
These criteria for inhalation toxicity of vapours are based on LC50 data relating to 1-hour exposure, and where such information is available, it shall be used.
However, where only LC50 data relating to 4-hour exposure to the vapours are available, such figures can be multiplied by two and the product substituted in the above criteria, i.e. LC50 (4 hour) × 2 is considered the equivalent of LC50 (1 hour).
In this figure, the criteria are expressed in graphical form, as an aid to easy classification. However, due to approximations inherent in the use of graphs, substances falling on or near group borderlines shall be checked using numerical criteria.
GROUP BORDERLINES INHALATION TOXICITY OF VAPOURS
Mixtures of liquids
Mixtures of liquids which are toxic on inhalation shall be assigned to packing groups according to the following criteria:
If LC50 is known for each of the toxic substances constituting the mixture, the packing group may be determined as follows:
(a)calculation of the LC50 of the mixture:
where fi = molar fraction of constituent i of the mixture;
LC50i = average lethal concentration of constituent i in ml/m3.
(b)calculation of volatility of each mixture constituent:
where Pi = partial pressure of constituent i in kPa at 20 °C and at standard atmospheric pressure.
(c)calculation of the ratio of volatility to LC50:
(d)the values calculated for LC50(mixture) and R are then used to determine the packing group ofthe mixture:
Packing group I R≥10 and LC50(mixture) ≤1 000 ml/m3;
Packing group II R ≥ 1 and LC50(mixture) ≤3 000 ml/m3, if the mixture does not meet the criteria for packing group I;
Packing group III R≥1/5 and LC50(mixture) ≤5 000 ml/m3, if the mixture does not meet the criteria of packing groups I or II.