Adulteration of Mexican Opium




Author: Ernesto Sodi Pallares , Sergio Meyran Garcia
Pages: 16 to 17
Creation Date: 1954/01/01

Adulteration of Mexican Opium

D.Sc. Ernesto Sodi Pallares National Institute of Cardiology
Q.F.B. Sergio Meyran Garcia National Institute of Cardiology


Although the dried latex from the unripe capsules of Papaver somniferum L. contains neither starch nor strontium sulphate, these two substances are very often found in opium seized by the Office of Attorney General of the Republic of Mexico, and more particularly in opium originating in the State of Hidalgo.

This paper is concerned with the quantitative determination of the starch and celestite contained in these specific Hidalgo opiums.


1. Determination of moisture content

One gramme of opium is spread out in a previously-weighed dish, and placed in a vacuum desiccator with phosphorus pentoxide until the weight remains constant. This operation should be performed with ten samples in order to obtain figures from which an average may be derived. The mean result yields a water content of 11.64 per cent in this adulterated opium.

2. Microscopic evaluation of starch content

One gramme of dry opium powder is triturated in a mortar containing two cubic centimetres of 96 degrees ethyl alcohol made up to ten cubic centimetres with simple syrup (850 grammes of sucrose made up with water to 1,000 cc), thoroughly mixed, and examined under the microscope on a Spencer slide.

The operation is repeated two or three times with other specimens and the average figure obtained. The number of starch grain multiplied by 10,000 yields the grain count per cubic centimetre, and the result, multiplied by ten, is the number of grains of starch per gramme of dry opium.

The average number of grains counted on the Spencer slide was 1.5 so that one gramme of dry opium contains 150,000 grains of starch.

Note.The starch is rendered distinguishable by an iodine reagent.

3. Chemical evaluation of starch content

Ten grammes of dry opium powder are exhausted with cold water, the residue is placed in a flask and 200 cc of 80 degrees ethyl alcohol containing 5 per cent of potassium hydroxide are added. It is then heated and refluxed in a water bath for twenty minutes. It is filtered hot and the residue is washed in 90 degrees ethyl alcohol, at heat, until the liquid becomes almost colourless. The alcohol fractions are jointly evaporated to dryness in vacuo. 200 cc of water and 16 cc of hydrochloric acid of specific gravity 1.16 are added to the residue and the whole is refluxed for three hours. It is then cooled, and neutralized to pH 7 with sodium carbonate. After filtering, it is diluted with water to 300 cc. The liquid is divided into three 100-cc portions and the reducing sugar content of each is determined by means of Fehling's solution. By this process the pentosans, such as starch and other carbohydrates which undergo hydrolysis when boiled in a hydrochloric medium, are counted so that the method is not very accurate.

The percentage of starch found was 37.4.

Calcining loss and ash analysis

100 grammes of impure opium yield 12.5 per cent of ash by calcination.

The composition of the ash is as follows:


Per cent

K 2O
Na 2O
Fe 2O 3
Al 2O 3
SiO 2


It is very important from the legal viewpoint to determine the substances used to adulterate opium in Mexico, because their identification makes it possible to ascertain geographic regions in which illicit traffic in the drug is carried on. In the present instance strontium sulphate was found in the ash of the poppy juice.

In Mexico, strontium sulphate is usually found in limestones and sandstones and mainly in the localities of Amajac, Jaso and El Salto, all of which are in the state of Hidalgo.

Celestite, or orthorhombic celestine, also occurs in fibrous, radiate and globular form. Its lustre may be glassy or pearly. Colour white, often bluish. Scrapings white, hardness from 3 to 3.5 and specific weight from 3.95 to 3.97; fusibility 3; it imparts a crimson colour to the flame. (The fusibility of 3 is determined by that of the edges, as in actinolite.)

Opium adulterated with earth from the state of Hidalgo (celestite) contains this latter substance and wheat starch (fecula extracted from the caryopsides of the Triticum vulgate Villars ).

The microscope reveals this powder to be composed of disc-shaped, lenticular grains of widely varied size. The smallest are irregular; the largest appear circular when viewed from the front and as greatly elongated ellipses from the side. Their greatest diameter is five one-hundredths of a millimetre. The hilum is scarcely visible; it is usually situated in the middle of the grain and surrounded by very thin, concentric layers.


  1. A case of adulteration of Mexican opium is described.

  2. An account is given of the methods employed to analyse the impurities.

  3. On the evidence of the analytical results the geographic location of the illicit traffic in opium can be identified.