Book reviews476

all philanthropic attempts to save millions of people from

arsenic toxicity. That dragon is the lack of maintenance

programs. When maintenance is an integral part of a

mitigation system and when trained staff is put in place by

the government or village to maintain the technology, only

then is sustainable management possible.

Linda S.S. Smith*

Arsenic Research and Mitigation,

Filters for Families, P.O. Box 2427, Kathmandu, Nepal

*Tel.: +977 981088435/1 5535909

E-mail address: filters@wlink.com.np

Available online 29 December 2006

doi:10.1016/j.agee.2006.10.005

Handbook of Toxic Plants of North America, G.E.

Burrows, R.J. Tyrl. Blackwell Publishing, (2006), 307

pp., Paperback, Price: US$ 89.99, ISBN 0-8138-0711-5

This book is an adjunct to the same authors’ monumental

(1342 pages) Toxic Plants of North America, reviewed

earlier (AEE 110 (2005) 327–328). Like the previous work,

it is of the very highest quality—an essential reference for

libraries and for veterinary professionals.

Plants can produce bad physical effects on animals in

several ways: mostly by synthesizing metabolites that are

detrimental when contacted or ingested, but sometimes by

absorbing harmful quantities of substances from the soil

(such as nitrates and selenium), and sometimes by

mechanical damage (e.g. from thorns and crystals). While

occasional purists distinguish ‘‘toxic plants’’ from ‘‘poiso-

nous plants’’ on the basis of which of these three categories

is included, for practical purposes, toxic is synonymous with

poisonous, and may include all kinds of injurious plants.

Pre-publication advertisements for the book provided the

title ‘‘Veterinary Handbook of Toxic Plants of North

America.’’ The ‘‘Veterinary’’ was likely dropped to appeal

to a broader audience, but in fact this book is mainly of

interest to those with expertise in veterinary science. The

coverage is mostly relevant to poisoning of free-range

livestock in Canada, the USA, and northern Mexico, by wild

plants, although some toxic cultivated plants are also

included, the latter of particular relevance to poisoning of

pets. In their Preface, the authors state: ‘‘We envision the

users of this book to be veterinarians, pathologists,

veterinary students, animal scientists, agricultural extension

agents, farmers, and ranchers; that is, individuals who are

likely to be the first to encounter a dead animal or one

showing signs of intoxication.’’ While the language used is

generally comprehensible to non-specialists, and a glossary

of botanical terms is given, some technical medical terms are

used (and a glossary for these is not given) that will only be

understood by professionals with a veterinary background.

The first 10 chapters respectively deal with plants

affecting the blood, cardiovascular system, digestive system,

eyes, liver, neuromuscular system, reproductive system,

respiratory system, skin, and urinary system. The final

chapter, 11, provides a page of information on plants causing

sudden death. Each of the first 10 chapters is organized into

three sections: principal signs (i.e. symptoms; usually about

six are given); plants causing problems (listed by the

principal signs); and, for each of what are termed ‘‘primary’’

plants (those that produce well-defined symptoms on

given organ systems) and ‘‘secondary plants’’ (those that

produce less severe or less manifested symptoms on given

organ systems), two facing pages of information. The left

page presents tabulated notes, usually under the categories:

signs and diagnostic aids; pathology; treatment and

prevention; disease problem (generally background infor-

mation); taxonomy and ecology. The facing right page

presents color photographs, line drawings, and distribution

maps.

Primary species, as defined above, frequently cause

devastating damage. Some of these affect more than one

organ system, in which case they are independently treated

in the chapters dealing with the individual organ systems.

Secondary species often produce less severe effects, but may

affect several organ systems, in which case they are treated

in a chapter where they are particularly important, with

cross-referencing to this chapter wherever relevant. ‘‘Ter-

tiary plants’’ are those that have relatively limited toxic

significance, and the reader is directed to find information

elsewhere.

In their preface, the authors stated: ‘‘Veterinarians,

pathologists, and other individuals who first encounter an

affected animal are presented with a suite of clinical and/or

pathological signs that they often must relate to a specific

toxic plant or plants. This book is written in response to that

need. Our objective was to take the information we compiled

in Toxic Plants of North America (Iowa State University

Press, 2001), reorganize it to emphasize disease syndromes,

and relate them to the plants responsible. This approach is

the opposite of that employed in Toxic Plants in which the

plants themselves were the primary focus.’’ The organiza-

tion of the information, described above, definitely

facilitates the task of identifying the plants responsible

for making animals sick. This book is extremely user-

friendly.

The authors rightly caution the reader: ‘‘We must offer an

obvious caveat regarding use of this book: not all toxic

plants are covered. . . we have deliberately selected the plant

species most commonly implicated in animal intoxica-

tions.’’ With this limitation in mind, this guide is an

extremely useful and authoritative aid to identifying toxic

plants after they have produced illness in animals. In some

cases this information may be directly useful for treating the

animals concerned although, in most cases of poisoning,

symptomatic treatment, i.e. treatment based on symptoms

rather than (presumed) cause, is in order. However, knowing

Book reviews 477

what plant species has caused a particular case of toxicity is

essential to prevent future cases.

In the field of human medicine, symptom-based

automatic (computer) diagnosis is increasingly being

developed. In time, the same will likely occur for veterinary

medicine, and Handbook of Toxic Plants of North America

provides the kind of information that can be used for this

purpose.

The most important similar work pertinent to North

America, also organized on the basis of symptoms of toxicity,

is: Knight, A.P., Walter, R.G., 2001. A Guide to Plant

Poisoning of Animals in North America. Teton NewMedia,

Jackson, WY, USA, 367 pp. (also available as a CD and online

by subscription or free to veterinarians at http://www.ivis.org/

signin.asp?url=http://www.ivis.org/home.asp (see textbook

section)). Knight and Walter’s guide is organized slightly

differently, and often presents somewhat different informa-

tion, and is familiar to numerous North American veterinar-

ians. While dealing basically with the same subject matter as

Handbook of Toxic Plants of North America, it would be a

mistake to choose one reference and ignore the other. By

consulting both works, the reader will likely obtain a better

idea of what plant is responsible for incidents of poisoning by

plants.

Ernest Small*

Biodiversity-National Program on Environmental Health,

Central Experimental Farm, Ottawa,

Ontario K1A OC6, Canada

*Tel.: +1 613 759 1370; fax: +1 613 759 1599

E-mail address: smalle@agr.gc.ca

(E. Small)

Available online 28 November 2006

doi:10.1016/j.agee.2006.10.006

Heavy Metal Contamination of Soil: Problems and

Remedies, I. Ahmad, S. Hayat, J. Pichtel (Eds.). SciencePublishers, Inc. Enfield, NH, USA (2005). 252 pp., Hard-

back, Price: US$ 85.00, USD, ISBN 1-57808-385-0.

Heavy metals can accumulate in the soil from industrial

and agricultural practices, creating a persistent problem

that is challenging and costly to remediate. Dealing with

heavy metal in soil systems requires an ability to predict

metal availability, to assess and mitigate potential risks

and to develop effective remediation methods where

excess heavy metal levels pose a threat to human or

ecosystem health. Heavy Metal Contamination of Soil:

Problems and Remedies outlines the scope of heavy metal

contamination, describes potential impacts of heavy metal

accumulation and discusses some established and experi-

mental methods of addressing contamination problems.

The focus is on relatively high levels of contamination,

such as that which can occur from applications of

contaminated wastes, rather than longer term low level

contamination from inputs of fertilizers and other

agricultural amendments.

The book begins with a broad overview of environmental

and health concerns related to land application of biosolids.

A range of contamination issues are covered with an

emphasis on the political and administrative considerations

rather than the scientific aspects of regulation. Based on an

evaluation of priority research areas for the US Environ-

mental Protection Agency, the author suggests more

resources need to be allocated to heavy metal studies,

considering the long-term persistence of heavy metal

contamination from long-term application of biosolids.

A good overview is also provided on the potential

benefits and drawbacks of the use of flyash on agricultural

soils, including the risk of heavy metal accumulation. Much

of the research on flyash has been conducted through pot

studies and the requirement for expanded field research is

identified. Applications of other metal-containing waste

products are addressed more narrowly, in chapters outlining

specific studies. For example, the results of a 15-year study

on the influence of long-term application of treated oil

refinery effluent on soil health indicated that crop

productivity and soil health were maintained although

there was a slow increase in heavy metal concentration in the

soil. The authors point out the need for monitoring the

impacts of application on sensitive microbial populations

and suggest potential methods of reducing the risk of

negative effects by alternating irrigation using oil refinery

effluent with irrigation using fresh water. Another chapter

presents the results of focused laboratory and field

evaluations of a specific municipal solid waste compost

to evaluate the effects on microbiological and biochemical

parameters.

The risk of impact from heavy metal contamination is

closely linked with bioavailability within a particular

environment. The importance and challenges of bioavail-

ability assessment for trace elements in soil systems are

outlined clearly in a well-referenced chapter. A variety of

methods commonly used for bioavailability assessments

are reviewed and some of the applications and associated

problems discussed. A subsequent chapter provides a

further review of factors influencing heavy metal avail-

ability in soils, followed by a description of a specific

study on the distribution Ni, Cu, Cd, Pb and Zn in soils

along a pollution gradient in the Kola Peninsula of Russia.

Changes in the soil microbial communities along the

gradient of Ni and Cu contamination indicate the

sensitivity of forest soils in the boreal regions to relatively

low levels of contaminant.

Much of the book emphasizes the interaction between

heavy metal contamination and the microbial community

in soils. Potential impacts of heavy metal contamination of

the functioning of the microbial ecosystem in the soil are