On May 26, 1995, Philip Morris USA* announced a voluntary recall of 36 cigarette product lines (approximately 8 billion cigarettes) because, during production, the company detected unusual tastes and peculiar odors and identified methyl isothiocyanate (MITC) in the cigarette filters. During June 6-8, 1995, public health officials in Minnesota, Oregon, and Texas requested the assistance of the Centers for Disease Control (CDC) in investigating consumer health complaints associated with smoking Philip Morris cigarettes near the time of the recall. This report summarizes CDC's ongoing investigation, which suggests that prolonged cigarette smoking caused most of the health complaints; in addition, the investigation has not identified a distinguishing chemical characteristic of the recalled cigarettes.
Reports of cases of illness near the time of the recall were identified through passive surveillance by direct telephone calls to the CDC. The CDC used a standardized form to interview persons who reported illness and, when possible, collected cigarette samples. To verify self-reported data, a medical records review was conducted. Cigarettes included in the recall had been manufactured during May 13-22. Philip Morris USA provided the CDC with samples of recalled cigarettes (manufactured on May 19, 1995) and, for comparative analyses, provided samples of cigarettes manufactured before (on March 3, 1995) and after (on June 12, 1995) the recall.
Reports of Illness
During June-July 1995, the CDC received reports of illness from 72 persons in 27 states who had smoked Philip Morris cigarette brands on or after May 13, 1995. The 72 persons comprised 36 men and 36 women; the mean age of these persons was 40 years (range, 15 to 67 years). A total of 41 (57%) persons reported onsets of illness before the recall, and 31 (43%) reported onsets after the recall. Of the 72 persons, 51 (71%) reported no preexisting health conditions; 42 (58%) reported experiencing serious health problems from smoking near the time of the recall. A case definition could not be developed because no common pattern of symptoms was identified; however, the most frequently reported manifestation was at least one respiratory or nasopharyngeal symptom (61 [85%]); other frequently reported symptoms included headache (18 [25%]), dizziness (15 [21%]), and ophthalmologic problems (15 [21%]). A total of 59 (82%) persons sought medical treatment for their symptoms; 14 (19%) were hospitalized.
All 72 persons reported smoking cigarettes manufactured by Philip Morris the day they became ill. Most persons (43 [60%]) smoked Marlboro brand cigarettes. The average duration of smoking was 20 years (range, < 1 to 45 years), and the average number of cigarettes smoked per day was 23 (range, <1 to 50 cigarettes).
Medical Records Review
Because a case definition could not be specified, further investigation was restricted to 29 persons who reported no preexisting health conditions and who reported experiencing serious health problems associated with smoking near the time of the recall. Of these persons, medical records were obtained for 20. Based on review of these records, the conditions most frequently diagnosed in these persons near the time of the recall were pneumonia (four persons), exacerbation of asthma (four), bronchitis (three), chronic obstructive pulmonary disease (three), eosinophilic pneumonitis (two), and laryngitis (two). The review suggested that most (18 [90%]) of these illnesses were associated with cigarette smoking, preexisting medical conditions resulting from prolonged cigarette smoking, or infectious agents.
The CDC analyzed cigarette samples using high-resolution gas chromatography/high-resolution mass spectrometry. Methyl isothiocynate was detected in samples of filter and samples of tobacco and paper obtained from prerecall, recall, and postrecall cigarettes provided by Philip Morris. Levels of MITC were higher in cigarettes packaged in hard packs than in soft packs (eg, 102 vs 15 ng per filter, P < .01, N = 21 [14 hard packs and 7 soft packs]). Methyl isothiocyanate also was detected in Philip Morris cigarettes produced at least 1 year before the recall. Seven packs of cigarettes from five other manufacturers were purchased at local stores in Atlanta; MITC was detected in cigarettes from each of these packs.
Cigarettes obtained from Philip Morris were analyzed for the eight compounds reported by Philip Morris** to have caused the taste and odor problems. Of the eight compounds, three (butyric acid; 1,2-propanediol diacetate; and 2-ethylhexyl acetate) were detected in prerecall, recall, and post-recall cigarettes; the other five compounds were not detected. Compared with prerecall and post-recall cigarettes, there was no distinctive increase in one or more of these compounds in the recall cigarettes.
Cigarette samples also were analyzed to identify a unique chemical profile that distinguished the recall cigarettes from the prerecall or post-recall cigarettes. Analysis of volatile organic compounds from the filter and from the tobacco and paper of these cigarettes did not identify such a profile. In addition, analysis of cigarette smoke from recall cigarettes did not contain a unique chemical pattern.
Laboratory analysis of cigarettes obtained from the 72 persons who reported illnesses is ongoing. However, as of March 22, 1996, no unique chemical pattern had been identified.
Editorial Note from the CDC
Based on the medical records review and laboratory analyses in this report, prolonged cigarette smoking-rather than smoking contaminated cigarettes-caused most of the health complaints from persons reporting illness associated with smoking Philip Morris cigarette brands near the time of the recall. Smoking is the leading preventable cause of diseases associated with premature death in the United States; in 1990, approximately 419,000 deaths were attributed to smoking. The estimated number of compounds in tobacco smoke exceeds 4,000, including many that are pharmacologically active, toxic, mutagenic, and carcinogenic.
Although Philip Morris reportedly recalled cigarettes, in part, because of the recent detection of MITC, the laboratory analyses in this report indicate that MITC was present in cigarettes manufactured by Philip Morris up to 1 year before the recall and in cigarettes from other manufacturers. Methyl isocyanate is a decomposition product of 3,5-dimethyl-1,3,5,2H-tetrahydrothiadizine-2-thione, which is used as a preservative in the manufacture and coating of paperboard*** and as a pesticide (dazomet) that can be used as a soil fumigant on tobacco plants, turf, and ornamental plants. Methyl isocyanate also is a decomposition product of sodium N-methyldithiocarbamate, a pesticide with uses similar to dazomet. Although adverse health effects from MITC exposure (eg, mucosal irritation of the respiratory and gastrointestinal tracts, conjunctival irritation, and neurologic symptoms) have been documented, there have been no assessments of the possible health effects of burned and inhaled tobacco that contains the levels of MITC detected in this investigation or of inhaling heated MITC found in filters.
The findings of this investigation are subject to at least four limitations. First, reports of illness were identified by passive surveillance; therefore, persons with health problems who contacted the CDC may not be representative of all persons who smoked Philip Morris cigarettes near the time of the recall and who may have incurred related adverse effects. Second, the recalled cigarettes provided by Philip Morris may not be representative of all the cigarettes eligible for recall. Third, because of the protracted time between the occurrence of clinical manifestations and the delivery of cigarette samples to the CDC, some of the volatile components may have evaporated from the cigarettes. Fourth, identification of possible contaminants was complicated by lack of access to the manufacturer's cigarette brand ingredients. Although Section 7 of the Cigarette Labeling and Advertising Act of 1996, as amended, requires that cigarette companies annually submit to the Secretary of the US Department of Health and Human Services confidential lists of ingredients added to tobacco in the manufacture of cigarettes, the law does not require companies to provide brand-specific information about additives or information about the quantity of each additive used in the manufacture of cigarettes. Therefore, the CDC could not compare the standard brand ingredients with those in recalled cigarettes; the identification of either unusual chemicals or unusual quantities was based on comparisons between the recalled cigarettes and samples of cigarettes produced before or after the recall.
Other than the well-established health risks associated with smoking,
this investigation did not detect additional health problems related
to smoking cigarettes recalled by Philip Morris. Laboratory analyses
of potential contaminants in cigarettes is ongoing. However, smoking
cessation is the only effective strategy to reduce the risks associated
with cigarette smoking.
Adapted from Morbidity and Mortality Weekly Report, vol 45, no. 12, March 29, 1996.
* Use of trade names and commercial sources is for identification only and does not imply endorsement by the Public Health Service or the US Department of Health and Human Services.
** Butyric acid; methanediol diacetate; 1,1-ethanediol diacetate; 1,2-ethanediol diacetate; 1,2-propanediol diacetate; 2-ethylhexyl acetate; 1,2-butanediol diacetate; and 1,3-propanediol diacetate in one lot of plasticizer (a substance sprayed on cigarette filters) (M. Firestone, Philip Morris USA, personal communication, June 30, 1995.
*** 21 CFR 176.230 Paperboard is used to produce hard-pack cigarette packaging.