384 



SCIENCE 



[N. S. Vol. XLIX. No. 126 



removal of the acid thus removes the greater 

 part of the toxicity. The continued intracel- 

 lular production of acid from the reserve of 

 lipoid-bouud " mustard " renders the com- 

 pound, once it has penetrated the cell, ex- 

 tremely persistent in its action and difficult 

 to counteract. 



The toxic action of " mustard gas " has a 

 prolonged latency, a fact in accordance with 

 the above conception. Fertilized starfish egg.s 

 treated for a few minutes (up to eight min- 

 utes) with a freshly prepared weak solution 

 of " mustard " continue to cleave for some 

 hours, at fixst regularly; later the cleavage be- 

 comes irregular and the eggs break down and 

 disintegrate. If acid derived from the pro- 

 gressive hydrolysis of " mustard " contained 

 as reserve in the cell-lipoids is chiefly respon- 

 sible for the toxic effect, the long latent period 

 of action is readily imderstood. An experi- 

 ment with adult fish (Fundulus) illustrates 

 both the long latent period and the necessity 

 that the " mustard " should be absorbed by the 

 living cells while it is still in the intact or 

 non-hydrolyzed state. Four fish were placed 

 in each of the following solutions : (A) Filtered 

 solution of " mustard " kept at room tempera- 

 ture five days; (B) a similar solution kept 

 at room temperature one day; (C) the same 

 solution as B, but kept at 0° C. and brought 

 to 20° C. one half hour before using; (D) the 

 same solution kept at 0° 0. until immediately 

 before using. 



Solutions A and B were almost non-toxic; 

 three of the four fish remained alive after 

 five days in the solution; in C all fish were 

 living after three hours, three were dead in 

 eighteen hours, and all in twenty-six hours; 

 in D two were dead and a third dying within 

 three hours. The toxicity is thus an inverse 

 function of the time during which the " mus- 

 tard " is undergoing hydrolysis. , 



While the loss of toxicity of an aqueous 

 " mustard " solution corresponds roughly with 

 the decomposition of " mustard " as deter- 

 mined by titration, a lag in loss of toxicity at 

 the end of the curve suggests that in those 

 extremely dilute solutions the organism takes 

 up a larger proportion of the poison than 



would be anticipated, possibly as a result of 

 adsorption. 



The velocity of the toxic action exhibits a 

 high temperature-coefficient similar to that of 

 chemical reactions in general. In one experi- 

 ment freshly fertilized starfish eggs were 

 placed in two portions of the same " mustard " 

 solution, one (A) kept at 9 to 10°, the other 

 (B) at 21°. From each solution eggs were 

 transferred to normal sea-water after exposures 

 of 1, 2, 4 and 8 minutes. It was found that 

 an exposure of 2-4 minutes at 21° had almost 

 the same effect in preventing development as 

 one of 8 minutes at 9°-10°. All eggs were 

 killed by 8 minutes' exposure at 21°, while 

 most survived this exposure at 9°. The rate 

 of toxic action at 9°-10° is thus about one 

 third of that at 21°. This result suggests that 

 cold, in conjunction with the other methods 

 of treatment, may prove to be of service in 

 treating the skin-burns caused by " mustard 

 gas," i. e., it indicates that the temperature 

 of the skin should be kept as low as possible 

 during the treatment (e. g., washing with ice- 

 cold kerosene is suggested). 



Experiments on the counteraction of the 

 toxic action by subsequent treatment with 

 weak basic substances which readily penetrate 

 protoplasm (ammonia, aniline) have not 

 yielded very conclusive results. In several 

 experiments fertilized eggs exposed to " mus- 

 tard" solutions for some minutes and then 

 brought for three or four hours into sea-water 

 containing a little ammonia m/2000 (NH3 in 

 sea-water) s|howed on the whole a more favor- 

 able development than eggs returned directly 

 from the " mustard " solution to sea-water 

 (i. e., larvffi showed less irregularity and more 

 active ciliary movement). This favorable 

 effect of ammonia was distinct but somewhat 

 slight. In other experiments Arenicola larvse 

 treated for some minutes with solutions of 

 aniline in sea-water (of the ansesthetizing con- 

 centration, ca. 1/8 saturated), and then ex- 

 posed to " mustard " solution, proved distinctly 

 more resistant to its toxic action than the 

 control. This effect is probably to be re- 

 g-arded as an example of the general protective 

 or antitoxic action which anaesthetics exhibit 



