According to the Central Intelligence Agency
(CIA), Al-Qa‘ida and associated extremist groups have a wide variety of potential agents and delivery means to choose
from for chemical, biological, radiological, or nuclear (CBRN) attacks. Al-Qa‘ida’s end goal is the use of CBRN
to cause mass casualties; however, most attacks by the group—and especially by associated extremists—probably
will be small scale, incorporating relatively crude delivery means and easily produced or obtained chemicals, toxins, or radiological
The success of any al-Qa‘ida attack and
the number of ensuing casualties would depend on many factors, including the technical expertise of those involved, but most
scenarios could cause panic and disruption. The CIA has published a brief primer on Terrorist Materials and Effects.